Science in Society Lecture Notes PDF

Lecture 1, September 6th **Course syllabus** Office location : cairn is 515 Email address : Office hours : Tuesday and Friday : 13 -- 14 Mondays : 13;30 -15;30 --------------------------------------------------------------- Announcements over Brightspace (class cancelled etc.) Emails -- sen...

Lecture 1, September 6th **Course syllabus** Office location : cairn is 515 Email address : Office hours : Tuesday and Friday : 13 -- 14 Mondays : 13;30 -15;30 --------------------------------------------------------------- Announcements over Brightspace (class cancelled etc.) Emails -- send from brock email, course code, brief description of topic, full name, student Id ( EX, course code -- request for appointment regarding the term paper) --------------------------------------------------------------------------------------------------------------------- **Midterm (15%)** -- **[October 12th (9am)]** (multiple choice 30 -- 45 questions) **final exam (15%)** -- tbd (multiple choice, minimum of 30% must be achieved on final exam to pass class) ------------------------------------------------------------------------------------------------------------------ **Two assignments** Term paper choice -- 5% **[(deadline to choose article is sept 30th) ]** Term paper -- 15% - **[(paper due nov 4th by 11pm)]** Write an evaluation of the approved article in your own words, no direct quotes, which must at least consider the following questions - Who are the researchers - Where do they work - What is/are the research questions they are trying to answer? **[Seminar schedule: Sept 12, sept 19, oct 3, oct 24, nov 7, nov 21 (every other week)]** Readings will be posted ahead of time on Brightspace Sem 6 -- Thursdays 11-12 plz311 (Susan Jonson -- Ninness) -- TA Written 1 page hand in paper (5 times 5) -- 25% \^ a one-page hand in summary of the current reading is due, using the assignment tools on Brightspace, the evening before your seminar by 11pm During Sem -- 5% (25% in total): attendance and participation during seminar, where readings are discussed , seminar questions for each reading are posted on Brightspace ------------------------------------------------------------------------------------------------------------------- **Important dates** Last day of lecture **--** dec 3 Last day of exam is December 19th Quote of the week We must believe that we are gifted for something and that this thing must be attained -- Marie curie ***Lecture 3 -- sept 13*** ***[Module 1 -- sustainability and environmental hazards ]*** Seminar Reading keywords Reading 1 : - Carbon footprint label - Environmental impact - Food choice - Environmental concern - Cognitive reflection Reading 2 : - Fire effects - Pyrogenic carbon - Soil biotic processes - Indigenous burning - Ecosystem carbon - Fire exclusion - Deep eutectic - Microplastics - Nano plastics - Hydrophobic - liquid extraction [Lecture 3 and 4 outcomes] - Recognize the major themes of environmental science - Understand the nature f human population growth - Define sustainability and the carrying capacity of the earth - Appreciate the concept of 'wicked problems' 1. The human population increase is a major contributor to Enivronmental problems 2. The industrial development and urbanization have environmental consequences 3. Unsustainable use of resources must be replaced with sustainable practices 4. Local changes can have global effects 5. Environmental issues innove both value and attitude as well as scientific [Early developments ] Before 1960, few people heard of the word ecology and the term environment meant little as a political and social issues - The environmentalist believe - The world would be destroyed if people do not accept some major changes in their approach to environment -- they alone had the key to salvation - The economic and social development meant the destruction of the environment , the end of a civilization , the extinction of many species and even the extinction of human beings - The anti environmentalist believe - The social and economic health and progress are essential to a prospering civilization - Environmentalist have dangerous and extreme views that will ruin the modern way of life. **[Today view; the environment is complex and multifaced]** The scientific understanding of the environment has made huge progress in the past 60 years **[Human population growth (1)]** In the last 50 years, the human population has more than doubled, a dramatic increase that puts even more pressure on the environment The current population of the world in 2024 is 8,118,835,999, a 0.91% increase from 2023 United nations predict there will be 9.8 billion people by 2050 and 11,2 billion by 2100 **[Human population growth (2)]** - The population change is a result of the interaction between births and deaths - Crude birth rate (CBR) -- crude death rate (CDR) = crude growth rate (CGR), all usually expressed per thousand o the population per year - Modern technology - Health care - Supply of food, clothing and shelter **[Black death (1347 -- 1352)]** black death was the largest demographic shock in European history and one of the largest population decline in history. A rough estimate is that 25 million people in Europe died from the plage during the black death and between 75-200 million people in the world died overall **[Canadian population growth ]** - Not due to a decrease in death rate or an increase in birth rate (the equivalent of an increase in the crude growth rate) its rather due to immigration growth **[Sustainability and carrying capacity of the earth]** Sustainability - Sustainable resources harvest -- the same quantity of a resource can be taken each year (or other set interval of time) for an unlimited or specified amount of time - Sustainable ecosystem -- an ecosystem able to keep its essential functions and properties despite the harvesting of its resources - Sustainable economy- an economy that can sustain its activity over time despite uses of environmental science - Sustainable development -- a society can develop its economy and social institutions and maintain the environment for an indefinite time. - The quality of life of people alive today or the future - The abundance of resources today or the persistence of these for future - The quality of local environment or the entire planet - Human creativity and innovation or the persistence of so many endangered species ***[Wicked problems ]*** 9 characteristics of wicked problems 1. Solutions cannot be immediately tested 2. No single explanation for the problem 3. Solutions are better or worse 4. No clear definition 5. No stopping rules 6. No alternative solutions 7. Each problem is connected to the other 8. The solver has no right to be wrong 9. Solving problem is a one shot operation ***[Trans mountain pipeline]*** - It's operation began in 1953, and the first shipment of oil reached the trans mountain Burnaby terminal on October 17th,1953 - A first expansion took place in 1957 - The anchor loop project (2006-2008) added 160km of new pipe through jasper national park and mount Robson provincial park between Hinton, Alberta and Hargreaves , BC - In 2012, kinder morgan announced a new project that consists in an expansion from Strathcona county in Alberta to Burnaby , BC ***[Trans mountain pipeline project ]*** - About 980 km of new pipelines will add to the existing 1,150km already in existence - The capacity will increase from 300,000 barrels a day in the existing pipeline to 890,000 barrels per day - In opposition to the existing pipeline which carries refined products, synthetic crude oils, and light crude oils, the new pipeline will carry heavier oils (called bitumen) - Almost ¾ of the new twin pipeline will follow the right of way to the original pipeline - The expansion project clouded three new berths at west ridge marine terminal, increasing the access to new market - Bert = a place for a ship to stay in a port ***[Federal court of appeal decision (august 2018)]*** - The federal government approval of the trans mountain pipeline is struck down - The national energy boards review did not consider : - Environemtal impact assessment had neglected to consider the effects of increased oil tanker traffic on the BC coast (impacts to southern resident killer whales) or the risk of a spill of diluted bitumen in the water - Federal government's consultation with indigenous people was deemed lacking -- need serious engagement ***[Reactions to the supreme court decision ]*** - Alberta\'s government would withdraw from the proposed national climate change plan, would not participate unless the federal government enabled the pipeline to proceed - BC premier praised the decision - significant adverse environmental effects on orcas - negative impacts on indigenous culture - increased greenhouse emissions - June 18th 2019 prime minister Trudeau announced the federal government's approval of the trans mountain pipeline project - one day after liberals passed a motion in the house of commons to declare climate change a national emergency, raising its emission reduction targets ***[what is crude oil?]*** - ***[c]***rude oil is a black liquid found in geological formations - It is a fossil fuel, which means it is formed from dead organisms that are buried under intense heat and pressure - There are three primary qualities that differentiate one oil from another - Weight - Sweetest - TAN count (1) ***[Heavy oil (bitumen) versus light oil]*** - Is highly viscous (tick) oil that cannot easily flow from production wells under normal reservoir conditions - Evaporates slowly and contains material that will be used to make heaven products like asphalt - Contain more sulphur, metals heavy hydrocarbons than the conventional light oil does - Must be either heated or diluted with lighter hydrocarbons - In case of spills, the heavier oils are more difficult to remove from waterways since it sinks beneath the water - Has low viscosity because it contains a high proportion of light hydrocarbon fractions - Requires less processing and produces a greater percentage of gasoline and diesel than heavy oil - Is it lighter meaning that it will float on the surface of the water and be easier to clean up ***[Millennium ecosystem assessment ]*** - Carried out between 2001 and 2005 - Assessed the consequences of ecosystem change for human well- being - Established the scientific basis for actions needed to enhance the conversation and sustainable use of ecosystems and their contributions to human well- being - Concluded that many of the changes are non-linear and once they start the processes of degradation will increase rapidly ***[Todays epoch : the Anthropocene ]*** ***[Anthropocentric view ]*** - Defined relative to human interests, wants and needs. Since it considers humans as the central or most significant beneath on the earth - This viewpoint priorities human needs, values and experiences over those of other species and the natural environment - With its human catered focus it has profound implications for how societies interact with the natural world ***[Eccentric or biocentric view]*** - Recognizes that the well-being of non-human life on earth has value in itself. This value is independent of any instrumental usefulness for limited human purposes. - "Ecocentrism, through its recognition of humanity\'s duties towards nature, is central to solving our unprecedented environmental crisis" ***[Sustainable development]*** ***Sustainable development is a development that meets the needs of the present without compromising the ability of future generations to meet their own needs*** Sustainable development entails there strategic aspects: - Presents a vision or direction of the nature of future societies - Emphasizes a system of governance characterized by openness, transparency, decentralization and accessibility - Ensures that economic, environmental and social aspects are considered together and that trade-offs are visible and transparent. The concept of sustainable development has generated both enthusiasm and frustration; - Provides a compelling vision for the twenty-first century that acknowledges the need to balance social, economic and environmental considerations - Term is so vague that it can be defined in ways to suit different and often conflicting interests Defined by the UN's 1987 world commission on environmental and development, as 'to meet the needs of the present without compromising the ability of future generations to meet their own needs - There are different ways of achieving that goal, but one of the biggest is an emphasis on renewable resources. - Fossil fuels, or anything that the earth has a finite amount of, cannot be considered sustainable because the use of them today impedes future generation's ability to rely on them. ***[Resilience ]*** The national academy of science defines resilience as, ' the ability to prepare and plan for, absorb , recover from and more successfully adapt to adverse events' The current U.S governments definition states, 'resilience includes the ability to withstand and recover rapidly from deliberate attacks, accidents, natural disasters as well as unconventional stresses, shocks and threats to the economy and democratic system' According to the oxford English dictionary the first to define resilience was Francis bacon in the 17^th^ century, as a relative term, not an absolute one. One has resilient to something. The ability of a system to absorb disturbance and still retain its basic function and structure The ultimate goal is to move a system into some ideal state and sustain it in that state. The more you optimize elements of a complex system of humans and nature for a specific goal, the more you diminish that systems resilience. +-----------------------+-----------------------+-----------------------+ | Resilience | Both | Sustainability | +=======================+=======================+=======================+ | - Multiple energy | - Energy | - Energy reduction | | sources | independence | | | | | - Renewable energy | | - Multiple water | - Water | production | | sources | independence | | | | | - Recycled/reclaime | | - Disaster | - Renewable | d | | fortitude design | resources | water | | | | | | - Emphasis on | - Resource storage | - Locally sourced | | passive systems | | material | | | - Environmental | | | - Reduced | effects | - Community | | environmental | | responsibility | | effects | - Community support | | | | | - Access to | | - Flood plain | | transportation | | evaluation of | | | | building location | | - Indoor | | | | environmental | | | | quality | +-----------------------+-----------------------+-----------------------+ ***Economic sustainability examples*** - Alternative energy - Sustainable fish farming - Sustainable farming practices - Mirco -- farming **Carbon footprint definition** It is a measure of the amount of carbon dioxide and other carbon compounds emitted due to the consumption of fossil fuels by a particular person, group, company or country. **Types of carbon footprint** The carbon footprint is a calculated value or an index that makes it possible to compare the total amount of greenhouse gases that an activity, person, product, company, industry or country adds to the atmosphere **Biocapacity debtors and biocapacity creditors** Biocapacity accounts for regenerative capacity of the planet 'countries that exceed their respective biocapacity are known as biocapacity debtors. This means that the country is net-importing biocapacity through trade, liquidating national ecological assets or emitting more carbon dioxide waste into the atmosphere than its own ecosystems absorbs. Countries that have an ecological surplus, on the other hand are known as biocapacity creditors. If everyone on the planet lived like these countries we would need fewer earths rather than more. **The worlds carbon emissions from energy productions** The energy sector contributes more greenhouse gas emissions than any other sector. These emissions largely derive from the consumption of fossil fuels, like oil and coal for energy. Total emissions are represented in millions of tones of carbon dioxide equivalent (MT CO2e) with the year -- over -- year change from 2022 -- 2023. **Key concepts:** **Ecological footprint of a country** it represents the amount of biologically productive land and water a population requires to produce all resources it consumes and to absorb the waste it generates, using prevailing technologies **Biocapacity** measures the biologically productive area of lands and waters that are available to sustain the components of the ecological footprint. Biocapacity components include cropland, grazing land, forest land, fishing grounds and built -- up land **Ecological footprint and biocapacity** are each quantified in a standard unit known as a global hectare (GHA) **Biocapacity debtors** are called the countries that exceed their respective biocapacity **Biocapacity creditors** are countries that have an ecological surplus **Carbon total emissions** are represented in millions of tones of carbon dioxide equivalent (MT CO2e) ***Lecture 5 -- sept 20th*** **The earth** The earth is a dynamic planet of interacting spheres - The non-living sphere - The atmosphere (i.e. the air) - The hydrosphere (i.e. the water) - The lithosphere (i.e. the land) - The living sphere or biosphere (i.e. the living organism) **Lithosphere** The lithosphere is the solid , outer part of earth, including the brittle upper portion of the mantle and the crust "the lithosphere includes the crust (whether continental or oceanic) and the uppermost part of the upper mantle. It extends from a few kilometers to about 100 -- 150 km under the older pars of ocean basins, and it is up to 250 -- 300 km thick under continental shield areas" The term lithosphere is derived from the Greek word 'lithos' meaning stone and 'sphaira' Meaning globe or ball **Soil layers** - Organic - Surface - Subsoil - Substratum - Bedrock **Lithosphere resources** A lithosphere resource is any resource or commodity collected, mined, or extracted from the earth Examples; - Fertile soil -- a limited supply - Minerals - Metals - Fossil fuel (coal, natural gas, crude oil) - Groundwater (aquifer) Characteristics - Typically found in soils and rocks and can be the soils and rock themselves - Many require expensive or environmental harmful extraction processes - Almost all are non renewable - Usually harder to extract than biosphere resources - Tend to be more multi-purposed and ubiquitous than renewable commodities **Soil composition** 'soil is a complex combination of weathered rock, air, water and decayed planets as well as living roots, burrowing animals, invertebrates , fungi and microbes The soil : - Allows plants to grow without it (e.g. Hydroponics, stunted trees clinging to rocks in the mountains), but most grow so much better with it - Is the first reservoir of water supplying planets between rain - Stores and recycles nutrients (e.g., nitrogen, phosphorus, potassium) - Anchors plants roots, which in turn hold the soil in place and when they decay provide humus **What makes a soil fertile** By fertile soil, we mean capable for growing plants, especially crops An ideal soil is : - Deep - Well-drained (meaning it is not always fully saturated with water) - Full of soil organic carbon (i.e. humus) - A loam containing fine-grained (clay), medium grained (silt) and course grained (sand) particles **What makes soils erode and degrade?** If the soil is completely protected from the wind and rain by planets -- grass , shrubs or trees will do -- it will continuously form and rarely erode Not only do the roots hold the soil, but also the blades of grass, leaves and leaf litter block the surprisingly forceful impact of raindrops The same organic matter absorbs water Little tunnels built by roots, fungi, worms, and all the other small living things in the soil that help dead plants and animals decay, increases the soil's porosity, giving the rain and snowmelt a chance to infiltrate If it is raining so hard that it cannot all infiltrate and starts to run off over the surface, the soil is anchored and has a protective barrier Moreover, all the blades of grass and leaf litter give the runoff a tortuous obstacle course in its path downhill, slowing it down and giving it an opportunity to find another low spot where it can infiltrate **Types of soil erosion** - Water induced erosion - Wind induced erosion **Water induced soil erosion** - Occurs during the largest of rainstorms - Occurs in low-lying swales where rushing water accumulates in temporary stream channels - even under natural conditions, soils erode quickly because the rainfall is insufficient to support enough plant life to completely cover the soil surface, yet it does rain often enough the provide substantial erosive energy **Wind induced soil erosion** - dry, unprotected soils are also vulnerable to wind erosion - the process of desertification occurs when dry grasslands are over-grazed by livestock - during the next drought, the remaining grasses cannot recover, leaving the soil further exposed in a vicious cycle **Soil degradation due to intensive farming** Soils can also be degraded (lose their fertility) without being transported to downstream or downwind. Soils can be depleted of organic matter and nutrients through intensive farming -- hence the need to add manure or some other form of compost and fertilizer. - Excessive salinization (accumulation of salt left behind by evaporation) destroys the soil fertility. The overapplication of irrigation water can create a wet corridor to underlying salts, which dissolves in the irrigation water and are carried toward the surface - Waterlogging can be triggered by excessive irrigation; it consists in the accumulation of water underground that raises the water level. **Soil degradation due to other human causes** - Excessive mining (metals, Dimond, graphite, potash) - Excessive fossil fuel extraction (gas, coal, oil) - Excessive deforestation (the removal and destruction of a forest or stand of trees from land that is then converted to farms, ranches, or urban uses) - Overgrazing (plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods) - Use to off-road vehicles **Soil conservation methods** Soil conservation largely consist of keeping as much of a vegetative cover in place as possible, consistent with the production of crops and inhibiting rapid runoff during rainstorm - Reduced tillage and no till - Leaving the last years crop residue in the field - Crop rotation - Adding manure or compost (mulching) - Planting a nitrogen -- fixing cover crop (like clover) - Planting across the slope rather than up and down - Planting filters strips along stream channels - Building terraces along slopes **Case study ; a man made disaster** Key points: - The erosion and degradation of soil should not be underestimated - Soil has a long memory The dust bowl -- a disaster authored by unsustainable farming techniques The dust bowl was the name given to the drought -- stricken southern plains region of the united states. Dust bowl was a decade long natural catastrophe of biblical proportions and the worst man-made ecological disaster in American history **The ancestral land** In the 19^th^ century description of the land still controlled by the Comanche and Apache tribes, whose fabled skills on horseback were honed hunting bison with bow and arrow, Egan noted "miles to water, miles to wood, and only six inches to hell" **The dust bowl causes** - The buffalo were exterminated to starve out the Comanche, while the cattle ranchers spread quickly - A series of federal land acts persuaded pioneers westward by incentivising crop farming and livestock farming in the great plains - The regional economy boomed as U.S.A became the worlds greatest food exporter - The soil was depleted of organic matter and nutrients through intensive farming - Beginning in 1932, the rains failed and with them the crops of winter wheat that farmers plant in the fall and harvest in early summer - A prolong drought affected the area between 1930 ns 1940 **The dust bowl effects** - Grass stated to disappear - The dry, unprotected soils blew away (wind erosion) and the southern plains would witness desertification - Soil blew into drifts against fences and houses, forming dunes, even on lands that held their grass cover, smothering it - Dust blew into the stomachs of cattle and the eyes of chickens. Only the birds that could fly fast enough to outrun the dust storms - Not only were the grasslands, crops and soil fertility being destroyed but also the most essential service nature provides -- breathable air -- was being sacrificed to the restlessly penetrating dust - The high plains lay in ruins. There was no colour to the land, no crops, in what was the worst growing season anyone had seen. - The dust bowl intensified the crushing economic impacts of the great depression and drove many farming families on a desperate migration in search of work and better living conditions **The 1935 big dust storm** - Happened on April 14^th^ 1935 (the 4^th^ year of drouth) - When farmers were already in bankruptcy and hunger and poor health became widespread - Started in the Dakotas, as a spring cold front came bearing down on the plains, a purple -- black wall of 300,000 tons of dust raced southwards - Anyone caught out doors was unlikely to survive - The great plains lost 850 million tons of soil that year, 100 times more than what is considered a soil erosion 'problem' - Nature had lost all balance. **Dust bowl area developments (1940 -- today)** - Rains returned in the 1940s and the land partly recovered - Since 1996, the conservation reserves program has paid farmers to keep permanent grass cover on the most highly erodible lands - A new unsustainable resource has been tapped -- groundwater. The Ogallala aquifer underlies nearly the same territory as the dust bowl, an enormous resource of approximately one quadrillion gallons that supplies a third of all irrigation water in the U.S. southern plains farmers have been able to grow not only wheat but also the more profitable and water -- demanding corn, soybeans, and cotton. By pursuing irrigation so vigorously, however, this resource too is failing - The relentless wind is finally used today, as the area boasts the largest fleet of wind turbines in north America - Unlike the fragile soils and the depletable fossil waters of the Ogallala, wind is inexhaustible. No matter how thoroughly it is utilized today, tomorrows supply cannot be diminished **Keywords** **Atmosphere --** the blanket of gas that surrounds the entire planet and extends to the edge of space. The atmosphere includes air, precipitation , clouds, and atmospheric aerosols. **Biosphere --** all living things from microbes to humans and everything in between **Lithosphere (geosphere) -** the solid earth (rock materials on the surface and in earths interior layers) and soil. **Pedosphere --** outermost soil layer of the geosphere/lithosphere **Hydrosphere --** all of earths bodies of water, including groundwater. The hydrosphere also includes the cryosphere **Cryosphere --** the part of the hydrosphere containing all of the worlds ice sheets and sea ice. **Soil conservation --** the management of soil to prevent its destruction **Watershed --** area of land that channels rainfall and snowmelt to creeks, streams, and rivers and eventually to outflow points such as reservoirs, bays, and the ocean Lecture 6 -- September 24^th^ **Circulation of matter on earth** A material cycle is a way of understanding the circulation of a particular substance or element (such as water, and carbon or nitrogen) by first examining where the substance/element is stored -- its stocks or pools -- and then examining how it moves among these pools -- it fluxes or flows Because geology and chemistry have major roles in studying these processes, recycling inorganic matter between living organisms and their nonliving environment called **biogeochemical cycles** **The most common elements in living organisms** The six most common elements associated with organic molecules take various chemical forms and may exist for long periods in the atmosphere, on land, in the water or beneath earths surface - **Carbon** is found in all organic molecules - **Nitrogen** is an important component of nucleic acids and proteins - **Hydrogen and oxygen** -- elements found in water and organic molecules are both essential to life - **Phosphorus** is used to make nucleic acids and phospholipids that comprise biological membranes - **Sulfur** is critical to the three -- dimensional shape of proteins **Types of carbon cycles** Biological carbon cycle - Deals with rapid carbon exchange among living organisms The living organisms are divided in - **Autotrophs organisms** (often called 'producers') that can produce their own food, using materials from inorganic sources - **Heterotrophs organisms** (called 'consumers' that must get their food from other organisms such as plants or prey animals. Biogeochemical carbon cycle - Deals with the long-term cycling of carbon through geologic processes - Geologic processes such as weathering, erosion, water drainage and the subduction of continental plates, all play a role in the cycling of elements on earth. **The carbon cycle** - Carbon is the second most abundant element in organism\'s by mass - Carbon is present in all organic molecules and some molecules that are not organic (such as CO2) and it has a vital role in the structure of biomolecules - Carbon compounds contain energy, and many of these compounds from dead plants and algae have fossilized over millions of years and are known as **fossil fuels** **The nitrogen cycle** Importance - In some parts of the world, excess nitrogen has negative impacts on biological diversity, human health, and climate - However , in other parts of the world, nitrogen shortages mean that food needs cannot be met Natural sources - Nitrogen is an abundant element on earth; it makes up about 78 percent of earth's atmosphere and is an essential nutrient for all forms of life - Plants and phytoplankton are not equipped to incorporate unreactive nitrogen gas from the atmosphere (where it exist as tightly bonded, triple covalent N2) - Nitrogen enters the living world through free-living and symbiotic bacteria, which incorporate nitrogen into organic molecules through specialized biochemical processes Some species of bacteria can perform nitrogen fixation the process of converting nitrogen gas into ammonia (NH3), which spontaneously becomes ammonium (NH4 +). Bacteria convert ammonium into nitrites (NO2 -) and then nitrates (NO3-). At this point, the nitrogen containing molecules are used by plants and other producers to make organic molecules (such as proteins). This nitrogen is now available to consumers. The process of denitrification is when bacteria convert the organic nitrogen (nitrates) into nitrogen gas, thus allowing it to re-enter the atmosphere. **The phosphorus cycle** Importance - Phosphorus is an essential nutrient for living processes - It is a major component of nucleic acids and phospholipids, and as calcium phosphate, it makes up the supportive components of our bones. - Phosphorus is often the limiting nutrient (necessary for growth) in aquatic, particularly freshwater, ecosystems Natural sources - Phosphorus occurs in nature as the phosphate ion (PO 4 3-) - In addition to phosphate runoff due to human activity, natural surface runoff occurs when it is leached from phosphate -- containing rock by weathering thus sending phosphate into rivers, lakes, and the ocean. This rock has its origins in the ocean - Phosphate containing ocean sediments from primarily from the bodies of ocean organisms and from their excretions - However, volcanic ash, aerosols and mineral dust may also be significant phosphate sources - In nature phosphorus exists as the phosphate ion (PO 4 3-) - Weathering of rocks and volcanic activity releases phosphate into the soil, water and air where it becomes available to terrestrial food webs - Phosphate enters the ocean through surface runoff, ground water and river flow - Phosphate dissolved in ocean water cycles into marine food webs - Some phosphate from the marine food webs falls to the ocean floor forming sediment **The sulfur cycle** - Found in atmosphere as a gas - Sulfate is in the soil Importance - Sulfur is an essential element for the molecules of living things - As part of the amino acid cysteine, it is involved in forming proteins Natural sources Atmospheric sulfur is found in the form of sulfur dioxide (so2) which enters the atmosphere from: 1. The decomposition of organic molecules 2. The volcanic activity and geothermal vents 3. The burning of fossil fuels by humans Sulphur is also found deposited on land by precipitation, geothermal venting or it is found in some types of rocks On land sulfur is deposited in four major ways: - Precipitation - Direct fallout from the atmosphere - Sulfur -- containing rock weathering - Geothermal vents The sulfur -- containing rocks originate from ocean sediments that are moved to land by the geologic uplifting of ocean sediments Atmospheric sulfur is found in the form of sulfur dioxide (so2) and as rain falls through the atmosphere. Sulfur is dissolved in the form of weak sulfuric acid (H2SO4) Sulfur can also fall directly from the atmosphere in a process called fallout. Terrestrial ecosystems can then use these soil sulfates (so4 2) which enter the food web by being taken up by plant roots. When these plants decompose and die, sulfur is released into the atmosphere as hydrogen sulfide (H2S) gas. **The oxygen cycle** Importance - The molecular oxygen in earths atmosphere was created by photosynthetic organisms: without photosynthesis, there would be no )2 to support cellular respiration - O2 is vital for creating the ozone layer, which protects life from harmful ultraviolet radiation emitted by the sun Natural sources - The earths atmosphere consists of almost 21 percent molecular oxygen (o2) Day = the co2 goes into the tree and o2 leaves, at night o2 enters and co2 leaves **The photosynthesis** Photosynthesis requires sunlight, carbon dioxide and water as starting reactants. After the process is complete, photosynthesis releases oxygen and produces carbohydrate molecules, most commonly glucose. These sugar molecules contain the energy that living things need to survive. The chemical equation shown summarizes the complex reactions of photosynthesis Carbon dioxide + water \-\-\-\-\-\-\-\-\-\-\-\-\--\> sugar + oxygen sunlight **Human activities that result in temporary or lasting soil degradation** - Mining (metals ,Dimond , graphite, potash) - Fossil fuel extraction (gas, coal, oil) - Excessive deforestation **Mining natural resources** Mining can cause - Soil erosion - Sinkholes - Loss of biodiversity - Unusable (not fertile) soil - Dissipation of dust and toxic gasses into the air - Contamination of soil, ground water and surface water by chemicals emitted from mining processes Mining is the extraction of valuable geological materials and minerals from the surface of the earth. Mining is required to obtain most materials that cannot be grown through agricultural processes or feasibly created artificially in a laboratory or factory Ores recovered by mining include metals, coal, oil shale, gemstones, limestones, chalk, dimension stone, rock salt, potash, gravel, and clay The ore must be a rock or mineral that contains valuable constituent, can be extracted, or mined and sold for profit. Mining is the extraction of any non-renewable resource (such as petroleum, natural gas, salt and even water) **Metals and mining sector -- the industry dedicated to the location and extraction of mineral and metal reserves** Rare earth minerals: - Radioactive isotopes - Uranium - Thorium - Beryllium - Zirconium Minerals - Dimond\'s - Graphite - Precious gemstones - Salt - Coal Precious metals - Gold - Silver - Platinum Industrial metals - Copper - Aluminium - Zinc - Iron - Nickel - Cadmium - Palladium - Titanium - Iridium **Environmental impact of mining on the lithosphere** Exploration phase - Excavations and borehole drilling impact the lithosphere Exploitation phase - In the open pit mining operations, an initial removal of the natural loose surface material (overburden) is required - Usually, the nutrient-rich and potentially fertile topsoil is removed and stored separately. The deeper mineral soil material also is removed to free the deposit for active mining and stored separately. - In underground mining, is the waste rock from the mining operation that requires storage. Ore dressing and smelting operations produce partly extensive amounts of tailings, slags and similar materials that need to be disposed of. Valley filling still appears to be the most sought after option Decommissioning phase - Soils should be able to recover rapidly after the infrastructures have been dismantled, removed, and recycled, if possible. **Giving a new life to an old salt mine** It is said that the story of Turda salt mine started during the roman occupation of Dacia (the territory currently occupied by Romania) almost 2000 years ago. The salt mine was closed in 1932 and reopened as a halotherapy center and tourist attraction in 1992. In 2008, the salt mine was modernized and open as a unique tourist attraction. "the salt from Turda salt mine could provide the salt needed for the entire planet for the next 60 years" **Turda salt mine** Today the salt mine houses: - A salt museum - A mini amusement park equipped with mini golf, billiards, table tennis, sports fields, and a children\'s playground - An underground lake where tourist can take a boat ride - A generous Ampitheater with 180 heated seats - A panoramic wheel (the only wheel in the world that works underground) **Fossil fuel formation** Types of fossil fuels: - Natural gas - Coal - Oil When most plants and animals die, they lose their chemical energy through decay when their bodies are burned or devoured, and this energy dissipates through respiration, which is the reverse of photosynthesis. If they die in water-logged environment lacking oxygen (this is called a reducing or anaerobic environment), however, the carbohydrates accumulate at the bottom of wetlands, shallow lakes, river deltas, estuaries and continental shelves. Over millions of years, the carbohydrates are buried by sediments, cursed and as they are buried deeper in the earths crust, slowly cooked until the oxygen is driven out and hydrocarbons form Higher temperatures and greater depths tend to produce gas while more moderate temperatures and depts produce oil **Coal** Natural gas A gaseous mixture of primarily methane or CH4 but also includes: - C2H6 (ethane) - C3h8 (propane) - C4h10 (butane) - C5h12 (pentane) - C6h14 (hexane) - C7h18 (octane, used to measure the energy value of gasoline) - C16h24 (hexadecane) which is the diesel fuel Coal is heavier, more complex and more carbon -- rich hydrocarbon Hydrocarbons derive their energy from the sun. In the sun, nuclear fusions produce helium from hydrogen releasing incredible quantities of energy. This light energy is used by plants during photosynthesis (a reaction converts solar energy unto the energy -- packed carbohydrate molecule known as glucose). The chemical energy in fossil fuels is derived over millions of years from glucose and so they are, in effect, stored solar energy **Crude oil** Oil is usually found one to two miles (1.6 - 3.2km) below the earth\'s surface, whether in land or ocean Once the oil is found and extracted, it must be refined, which separates and prepares the mix of crude oil into the different types of gas, diesel, tar, and asphalt. One source of oil is tar sands -- moist sand and clay deposits with 1-2 percent bitumen (thick and heavy petroleum-rich in carbon and poor in hydrogen). These deposits are removed by strip mining. Another source is oil shale, which is sedimentary rock filled with organic matter that can be processed to produce liquid petroleum. Extracted by strip mining or creating subsurface mines, oil shale can be burned directly like coal or baked in hydrogen to extract liquid petroleum. However, the net energy vales are low and expensive to extract and process. **Petroleum fields** - Oil and gas often occur together in fields below the land surface or sea floor within sedimentary rocks like shale, sandstone, or limestone - There they coexist with groundwater filling in the tiny, interconnected pore slaves in the permeable reservoir rock. - Oil is generally lighter than water, so it migrates above it - Gas is lighter but still is under the enormous pressures deep in the earth **Classic onshore drilling** Vertical drilling is the process that involves drilling a well straight down. This process is not very effective, as it cannot tap into the full potential of horizontal reservoirs. Horizontal drilling is the process that involves drilling a well vertically into the earth initially. However instead of continuing solely in the vertical direction, the well undergoes a change in direction typically referred to as the kick off point **Hydraulic fracking** Hydraulic fracturing is useful in encouraging wells and extracting trapped oil from these challenging reservoirs. This process involves the injection of water mixed with chemicals into the well at high pressure, including fractures in the rock formations that can extend over hundreds of feet. To prevent these fractures from closing drillers introduce a proppant -- a blend of fluids, sand, and pellets. These fractures act as conduits allowing oil to flow more freely from the rock. **Off shore drilling** Off shore drilling is the process of extracting oil beneath the sea floor. Oil drillers quickly recognized the abundant oil reservoirs near shorelines, prompting the exploration of profitable methods for extracting oil beneath the sea floor A key catalyst in this development was the introduction of remotely operated vehicles (rovs). rovs are operate from the rig above the water\'s surface serving as robotic devices that provide operators with underwater visibility **Keywords:** **Eco-efficiency analysis:** analysis of realizing the concept of creating goods and services with fewer resources and less waste and pollution **Exploration:** process of finding mineral resources for the purpose of mining **Exploitation:** act of using something (mineral resources) for any purpose **Open-pit excavation:** process of extracting minerals from surface deposits **Underground mines excavation:** process of extracting minerals from underground deposits **Decommissioning:** removal of something from active status **Recultivation:** making raw mineral soils fertile again through bioengineering and re- fertilization **Rehabilitation:** restoring land after some process has damaged it **Remediation:** removal of pollution or contaminants from the environment **Fossil fuel:** is a fuel derived from hydrocarbon deposits such as coal, petroleum, natural gas and to some extent, heat. **Lecture 7 -- sept 27^th^** **The earth** The earth is a dynamic planet of interacting spheres: - The non-living sphere - The atmosphere (i.e., the air) - The hydrosphere (i.e., the water) - The lithosphere (i.e., the land) - The living sphere or biosphere (i.e, the living organisms) A material cycle is a way of understanding the circulation of a particular substance (such as water or carbon or nitrogen) by first examining where the substance is stored -- its stocks or pools -- and then examining how it moves among these pools -- its fluxes or flows. **The hydrosphere** A hydrosphere is the total amount of water on earth (or any other planet). It include: - The water on the surface of the planet - The underground water - The water in the air The term hydrosphere is derived from the Greek words "Hydros" meaning stone and "sphaira" meaning ball **Forms/phases of water** A planet hydrosphere is a combination of - Liquid - Vapor (water in gas phase) - Ice (water in solid phase) Phase transitions refer to the changes between different states of matter. **Defining the phase transitions** **Metling:** solid to liquid (e.g. ice melting into water) **Freezing:** liquid to solid (e.g. water freezing into ice) **Vaporization:** liquid to gas (e.g. boiling water turning into steam) **Condensation:** gas to liquid (e.g. steam condensing into water droplets) **Sublimation:** solid to gas without passing through the liquid phase (e.g. icicles sublimating into water vapor in cold conditions) **Deposition:** gas to solid without passing through the liquid phase (e.g. frost forming from water vapor) **Real life examples of phase transitions** Metling - Ice melting into water - Sugar melting into caramel - Glass becoming liquid glass - Chocolate melting - Cheeses melting - Butter melting - Candle turning into liquid paraffin - Plastics becoming liquid plastics Freezing - Water turning into ice - Milk freezing into frozen milk - Honey crystallizing - Freezing food - Solidification of melted candle wax - Embryo freezing - Lava hardening into volcanic stone Vaporization - Boiling water - Brewing tea or coffee - Evaporation of sweat - Recovering table salt from the sea water - Drying wet clothes in the sun - Clouds formation - Perfume and fragrance - Tile drying - Separation of components in industrial processes Condensation - Steamy bathroom mirrors - Moisture beads on car windows - Morning dew on the grass (water vapor in the air becomes saturated and condenses) - Fog in the air (only in extreme humid conditions) - Clouds in the sky (water vapor cooling in air) - Rain falling to the ground (too much water condenses around air dust particles for the water to remain in the sky in the form of clouds) Sublimation - Dry ice (frozen carbon dioxide) transforming from a solid to a gas without melting - Naphthalene balls shrinking as they release vapor - Camphor crystals disappearing into vapor - Icicles sublimating into water vapor in cold conditions Deposition - Water vapor in the atmosphere changing directly into ice, such as the formation of frost - Formation of snow in the clouds - Formation of frost on windows and on the ground - Discharging a "CO2" fire extinguisher - Deposition of silver vapor onto glass to form a silver mirror **The hydrologic cycle** The hydrologic cycle includes the distribution and circulation of water on earths surface, oceans, and atmosphere The cycle is a system of fluxes of water among different reservoirs, where water is stored (as liquid or solid in the terrestrial and oceanic components and as vapour in atmosphere) "theses fluxes or transfer paths penetrate the entire hydrosphere, extending upward to about 15km (9 miles) in earths atmosphere and downward to depths on the order of 5 km (3 miles) in its crust) The driving forces of this perpetual hydrologic cycle that allows for evaporation and mixing of water in the atmosphere are: - The solar energy - The gravity **Fluxes move water between reservoirs** Fluxes are the ways that water moves between reservoirs (or pools) such as evaporation, precipitation, discharge, recharge or human use Water moves between the atmosphere and the surface through: - Evaporation - Evapotranspiration - Precipitation Water moves across the surface theough: - Snowmelt - Runoff - Streamflow Water moves into the ground through: - Infiltration - Groundwater discharge Underground, groundwater flows within aquifers Groundwater can return to the surface through natural discharge into rivers, the ocean and from springs **Evaporation -- precipitation fluxes** Fluxes are the ways that water moves between reservoirs (or pools), such as evaporation, precipitation, discharge, recharge or human use Marine evaporation-precipitation flux - Most marine precipitation is derived from marine evaporation - Marine evaporation exceeds marine precipitation Continental evaporation-precipitation flux - Most continental evaporation is returned to the contients as precipitation - Continental precipitation exceeds continental evaporation The system is balanced by transport of water vapor from the oceans to the continents and the drainage of liquid water from the continents to the ocean **Spatial and temporal variability of the hydrologic cycle** Due to the complex interactions of dominant weather patterns, latitude and surface and subsurface characteristics (topography soil, geology, vegetation, land cover), the fluxes and stocks (reservoirs) of water vary: - By location - Time of the year - From year to year The evapotranspiration is mainly controlled by: - Latitude (maximum near equator and almost zero at the poles) - Diurnal and seasonal cycles (as a function of the solar radiation fluctuations) **World water reserves (watch are we running out of clean water)** The main fresh -- water resources on earth are: - Oceans - Ice caps, glaciers, and permanent snow - Groundwater The total mass of water in the oceans equals about 50 percent of the mass of sedimentary rocks now in existence and about 5 percent of the mass of earth\'s crust as a whole" **Water availability** Humans and other organisms rely on water for life The amount of water that is available depends on: - How much water there is in each pool (water quantity) - When and how fast water moves (water timing) through the water cycle - How clean the water is (water quality) By understanding human impacts on the water cycle, we can work toward using water sustainably **Natural sources of water** [Well water:] groundwater drawn from a well [Spring water]: natural water from a spring [Mineral water]: water from a mineral spring containing various minerals [Sea/ocean/lake water:] sea, ocean or lake water that is safe for drinking water consumption [Rainwater:] water produced by rain (can either be pure or contaminated) *[Ice/snow water and glaciers:]* soild state water useful for drinking water consumption **Is the earths water pure?** "earths water are not pure H2O but contain dissolved and particulate materials The water on earths surface are major receptacles of inorganic and organic substances and water movement plays a dominant role in the transportation of these substances about the planets surface" The most abundant elements of the hydrosphere in decreasing order of abundance are: - Chlorine (Cl) - Sodium (Na) - Sulfur (as SO 4 2-) - Magnesium (Mg) - Calcium (Ca) - Potassium (K) - Carbon (as bicarbonate) **Types of drinking water (watch when is water safe to drink)** **Tap water:** public drinking water supplied to homes and businesses **Purified water:** treated tap water to remove impurities **Distilled water:** pure water obtained by distillation (most of impurities are removed) **Sparkling water:** carbonated water with bubbles **Infused or flavored water:** water with added ingredients like fruits or herbs **Filtered water:** tap or well water filtered to remove contaminants **Alkaline water:** water with a higher pH level, often marketed for health benefits **Humans alter the water cycle** Water storage or movement The water storage is modified by humans by: - Redirecting rivers (ex, by building dams to store water) - Draining water from wetlands for urban, rural, or industrial developments - Using the water to supply water to our homes and communities - Using the water for agricultural irrigation and grazing livestock - Using the water in industrial activities (thermoelectric power generation, mining, etc.) and aquaculture Water quality The water quality is influenced by humans: - In argicultural and urban areas -- irrigation and precipitation wash fertilizers and pesticide into the rivers and groundwater - Power plants and factories return heated and contaminated water to rivers and lakes Downstream from these sources, contaminated water can cause: - Harmful algal blooms - Spread diseases - Harm, habitats for wildlife **Man -- made polluted water** Wastewater: Any liquid waste produced from two types of sources: - Sanitary sewage -- generated from homes, businesses, institutions, and industries - Storm water -- generated from rain or melting snow that drains off rooftops, lawns, parking lots, roads, and other urban surfaces Waste is collected by sewer systems and usually it is treated before being released to the environment **Environmental impact of mining on the hydrosphere** Exploration phase: - Spillage of drilling additives impacts the water sources. Exploitation phase: - Most mining operations demand large amounts of energy and water - For high-volume , high-mass coal mining operations entire power plants are needed to meet the energy demand of the operations - Open-pit mines may use very large amount of water for the mining process itself (e.g., high-power water jets, air stripping machine cooling) and to safeguard infrastructure (e.g., constant water spraying to suppress dust generated on haul roads and stockpiles) - To keep the mine dry, safe and operable it is required to lower of groundwater levels around the mining operation. This could trigger not only water losses but potentially hazardous water contamination Decommissioning phase - Polluted wastewater may directly impact biota -- and indirectly, the human body **Water action on the lithosphere (watch human water cycle: wastewater)** - It dissolves (chemically weather) mineral components from rocks - It contributes to the physical alteration of the lithosphere because water expands when it freezes. Rocks exposed at earth\'s surface that are intruded by liquid water may experience repeated cycles of freezing and thawing with consequent cracking - It can transport particles of broken rock in suspension and in many rivers, the transport of suspended solids greatly exceeds that of dissolved solids Excluding oxygen, the seven most abundant elements of lithosphere, in decreasing order of abundance are: - Silicon (Si) - Aluminum (Al) - Iron (Fe) - Calcium (Ca) - Sodium (Na) - Potassium (K) - Magnesium (Mg) **World water day** - Saturday March 22, 2025 "Everybody is a genius, but if you judge a fish by its ability to climb a tree, it will spend its whole life believing that it is stupid" **Lecture 8 -- oct 1st** **The earths spheres** The earth is a dynamic planet of interacting spheres: - The non-living sphere - The atmosphere (i.e., the air) - The hydrosphere (i.e., the water) - The lithosphere (i.e., the land) - The living sphere or biosphere (i.e, the living organisms) A material cycle is a way of understanding the circulation of a particular substance (such as water or carbon or nitrogen) by first examining where the substance is stored -- its stocks or pools -- and then examining how it moves among these pools -- its fluxes or flows. **The atmosphere** The atmosphere is the blanket of gas that surrounds the entire planet and extends to the edge of space. The atmosphere includes: - Air - Precipitation - Clouds - Atmospheric aerosols (tiny floating particles) - Exosphere (700 -- 10000km) Thermosphere (80 -- 700km) Mesosphere (50 -- 80km) Stratosphere (12 -- 50km) Troposphere (0 -- 12km) **Aerosols** There is more than just air in the sky. There are also billions of tiny floating particles called aerosols or particulates. Some aerosols are so small that they are made of only a few molecules and can only be seen through an electron microscope. Some aerosols are large enough to be seen with the eye, while they are still small enough to be suspended in the air. In general, the smaller and lighter a particle is, the longer it will stage in the atomsphere. **Gas composition of the atmosphere** Nitrogen = 78% Oxygen = 20.9% Argon gases = 0.90% Other gasses = 0.17% Carbon dioxide = 0.03% **The earths atmosphere** Characteristics: - The atmosphere has mass, is bound by earths gravity and exerts pressure which is greater near earths surface and decreases with altitude. - The atmosphere, which is very thin relative to earths radius, varies vertically in layers which differ in composition, density and temperature. The lowest 8 --16km of the atmosphere -- the troposphere -- contains most of earths weather systems - Earths atmosphere sustains and protects living things. Its composition has changed over time, as it as been influenced by life and by geological and geochemical processes. Through photosynthesis, plants produce the oxygen in the atmosphere and make life possible. Other bodies in the solar system also have atmospheres. Their composition and motions vary considerably from those of earths atmosphere due to planetary size, place in the solae system, speed of rotation and other planetary processes. **Suns energy** - Earth receives energy in the form of electromagnetic radiation from the sun - Some of this solar energy is absorbed by the atmosphere, some is scattered back to space and some is transmitted through the atmopshere to be absorbed or reflected by earths surface - The solar energy reflected by earth\'s surface is absorbed by, scattered ir transmitted by the atmosphere - On human time scales, the energy emitted by the sun is nearly constant, varying only very slightly due to solar activity - 20% scattered and reflected by clouds - 51% absorbed by earth - 6% scattered from atmosphere - 19% absorbed by the atmosphere and clouds - 4% reflected by surface **Suns energy and atmospheric processes** Energy from the sun is transformed into other forms of energy in the earths system. Solae energy drives various biological, chemical and ohysical processes that affects earths atmosphere. These include processes such as: - Photosynthesis - Evaporation of liquid water to produce water vapor - Formation of smog - The formation and destruction of ozone The amount of solar energy received at a point on earths surface varies due to earths: - Spherical shape - Daily rotation about its tilted axis - Annual revolution around the sun - The slight elliptical shape of earths orbit. Leading to important cycles such as day and night, and the seasons In addition, cloud cover and aerosols can reduce the amount of solar energy that reaches earths surface. **Earths energy** - Earth also emits energy in the form of electromagnetic radiation - Almost all the energy emitted comes from the solar energy absorbed by earths surface - This terrestrial energy is absorbed by atmospheric trace gases in the atmopshere (such as water, vapor, carbon dioixde and other gases) - This energy may be remitted from the atmosphere, either to space or back to earth, where it is again absorbed, producing a 'greenhouse effect' - This natural greenhouse effect is crucial for life to exist om earth. **Atmospheric circulation transports matter and energy** Horizontal and vertical energy imbalances in the earths system produced by unequal heating of earths surface create movement in the atmosphere and the ocean Energy is exchanged within the atmosphere, as well as gained and lost across its interface with land and ocean through physical, geological and biological processes organized in earths cycles (eg the water cycle). Theses exchanges help drive atmospheric circulations. Patterns of circulation in earths atmosphere can be observed at many different spatial scales from global to local. Temperature differences, the rotation of earth on its axis, and the configuration of the continents and oceans establish the large-scale atmospheric circulation. Atmospheric transport of water affects the formation and development of clouds, precipitation, and weather systems, which are all important components of the global water cycle. Atmospheric circulations distribute matter and energy globally and establish weather and climate patterns **Atmosphere interactions** Interactions and feedbacks among the components of the earth system can produce: - Short-term oscillations (such as EL Nino snd La Nina conditions in the Pacific Ocean) - Long term changes in the state of the system (such as global warming) - Abrupt, unexpected events (for example, a sudden release of methane from permafrost) **Spatial and temporal changes of earths atmosphere -- weather** The atmosphere changes over time and space, giving rise to weather and climate. Both weather and climate vary by region based on latitude, altitude, land use, proximity to physical features (such as the ocean and mountains) and ocean currents - Weather is the state of earth\'s atmosphere at a particular place and time - Weather changes over time periods ranging from seconds to weeks - Weather phenomena are important to human society - Severe weather (thunderstorms, tornadoes, hurricanes) can bring rapid, dramatic changes to ecosystems and to individuals, property and infrastructure **Spatial and temporal changes of earths atmosphere -- climate** The climate of a particular place involves the long-term range of weather conditions at that place. Earths global climate is determinded by the energy recieved from the sun and is controlled by: - Atmospheric compostion - Atmospheric and oceanic circulation - Climate changes over intervals ranging from years to millennia These gradual variations have been interrupted by abrupt climatic shifts caused by volcanic eruptions and sudden redistributions of mass and energy in the earths system **Earth atmosphere and the living organisms** Most living organisms on earth are dependent on earths atmosphere and its processes for survival. For examples, humans: - Require oxygen for breathing - Rely on ozone in the stratosphere to protect from harmful radiation from the sun - Depend on prevailing wind patterns to drive ocean upwelling and so supply food - Relay on wind to power turbines sails and ventilators - Need rain for drinking water Living organisms can and do change the composition of earths atmosphere and its processes Many humans activites (farming, forestry, building of cities and burning of fossil fuels) alter atmosphere composition and thereby impact the functioning of ecosystems, human health and climate on local, regional and global scales **What\'s in the air you breathe? Fresh air vs pollution** - 0.07% of every breath you take is man made pollutants **Understanding the atmosphere, air and atmospheric pollution** - Major worry when people go to space because we aren\'t supposed to be that close to the sun - Without the ozone layer we wouldn't be here - Nox and Sox are poisonous for us **Major air pollutants** Indoor air pollutants - Molds - Radon - VOCs (volatile organic compounds) - Asbestos Outdoor air pollutants - NOx (nitrogen oxides) - SOx (sulfur oxides) - Particulate matter (small dust particles or smog carried by air) - CO (carbon monoxide) - Lead - Ozone **Carbon dioxide gas (CO2)** - Co2 is always present in the atmosphere and on the earth - A universal source of carbon to the carbon cycle and life processes - A colorless and stable gas at room temperature - Co2 in the atmosphere is constantly formed (added) and consumed (removed) by biological processes such as photosynthesis and cellular respirations - At high concentrations of Co2 humans experience suffocation and anaphylaxis - Co2 creates the greenhouse effect in combination with methane , water vapor and other gases **Carbon monoxide gas (CO)** - Co is not a product of natural processes, but rather it is man-made - A colorless, odorless and poisonous gas - It is produced by incomplete gas combustion, smoke from cigarettes, burning wood and other fossil fuels, volcanoes, water heaters, broken heating systems, cookers and gas fires - An accumulation of CO in the body depletes oxygen levels (by displacing pxygen in the blood) and causes poisoning - Some of the symptoms of CO poisoning are headaches, weakness, dizziness, nausea, confusion, loss of muscle control, loss of consciousness or memory loss - CO is one of the six major outdoor air pollutants (also called criteria pollutants) regulated in many countries around the world **Co2 verus CO** Co2 - A density of 1.964 km/m3, when it is a gas, at 1 atm and 25 degrees Celsius while the air density is 1.200km/m3 at 1 atm and 25 o Celsius - Co2 gas is denser than air and it will sink to the ground, therefore the co2 detectors should be placed on the ground - Co2 is not toxic but it can be hazardous when it is present in high concentrations - Co2 has various applications in the food and beverage industry - It is used in the production of fire extinguishers, dry ice, urea and fertilizers - Co2 is used in the production of effervescent drinks and preservation of fruits and vegetables CO - A density of 1.145 km/m3, when it is a gas, at 1 atn and 25 degrees Celsius, while the air density is 1.200 km/m3 at 1 atm and 35 degrees Celsius - Co gas is a little lighter than air and it will rise from the ground , therefore the co detectors should be placed at high levels - Co is a toxic gas that finds mire industrial uses such as the manufacture of other chemicals - It is used in the extraction of pure metals from metal ores, iron and steel manufacture, hydrogen productuon, petrochemical and automotive industries - Co is often used in food processing (used in the preservation of fresh meat) **The greenhouse effect** Some solar radiation is reflected by the earth and the atmosphere Most radiation is absorbed by the earths surface ad warms it Some of the infrared radiation passes through the atmosphere. Some is absorbed and re-emitted in all directions by greenhouse gas molecules. The effect of this is ti warm the earths surface and the lower atmosphere Infrared radiation is emitted by the earths surface The greenhouse effecr is the natural process theough which heat is trapped near earths surface by subtsances known as 'greenhouse gases" Greenhouse gases consist of: - Carbon dioixde - Methane - Ozone - Nitrous oxide - Fluorinated gases such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) - Water vapors Without the greenhouse effect , earths temperature would be below freezing and the life as we know it would not be possible However, the earths greenhouse effect is getting stornger as we add greenhouse gases to the atmosphere. That is warming the climate of our planet Even though only a tiny amount of the gases in earths atmosphere are greenhouse gases, they have a huge effect on climate Sometime during this century, the amount of the greenhouse gas carbon dioxide in the earths atmosphere is expected to double Greenhouse gases are being release into the atmosphere from: - Burning of fossil fuels that release carbon dioxide and other air pollutants into the atmophere - Raising farm animals, as the cows release methane gas as they digest food - Cement production, as the cement is made from limestone and it releases carbon dioxide Not all greenhouse gases have the same heat -- trapping abilities, greenhouse gases don\'t all stay in the atmosphere for the same amount of time. Thus, some greenhouse gases are stronger than others **Methane gas (CH4)** - Although the concentration of methane in earths atmosphere is small (around 1.8 parts per million) it is an important greenhouse gas bevause it is such a potent heat absorber - The concentration of methane is our atmosphere has risen by about 150% since 1750, largely due to human activities - Methane accounts for about 20% of the heating effects by all of the greenhouse gases combined - Methane is flammable - Both natural and human sources supply methane to earths atmosphere Major natural sources of methane include emissions from wetlands and oceans and from the digestive processes of termites Sources related to human activites include - Rice production - Landfills - Raising cattle and other ruminant animals - Energy generation (the principal component of natural gas) **Carbon dioxide (co2)** The amount of co2 in the atmosphere far exceeds the naturally occuring range seen during the last 650,000 years Most of the co2 that people put into the atmosphere comes from: - Buring fossil fuel by cars, trucks, trains , ships and planes - Buring fossil fuels in electric power plants - Cutting down forests because trees contain large amount of carbon **CFCs, HCFCs, VOCs (fluorinated gases)** The fluorinated gases in the stratosphere produce the ozone hole, while the troposphere produce the global warming **Keywords** **Outdoor air pollutants (criteria pollutants):** NOx (nitrogen oxides), SOx (sulfur oxides), particulate matter (small dust particles, smog carried by air), CO (carbon monoxide) and ozone (a human made secondary level pollutant) **Indoor air pollutants:** molds, radon, VOCs (volatile organic compounds, such as formaldehyde) and asbestos **Acid deposition:** a system in which energy and/or matter flows freely across the systems boundaries **Greenhouse gases:** Co2b(carbon dioxide), CH4 (methane) and NO (nitrous oxide), CFCs (chlorofluorocarbons) and water vapor **Methane:** is the principal component of natural gas: it is a flammable gas, normally found in the atmosphere **Fluorinated gases:** includes chlorofluorocarbons (CFCs) , hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs). CFCs are the only greenhouse gases not created by nature **Aerosols (particulates):** tiny floating particles of different shapes (volcanic ash, pollen, sea salt, and soot) that are found flowing in the air. **Gas composition of the atmosphere:** nitrogen (78%), oxygen (21%) and other gases (1%) **Solar energy:** the energy produced by the sun, this energy is both absorbed ad reflected by earth **Absorbed solar energy:** the part of solar energy absorbed by the earth, this energy drives various biological, chemical and physical processes that effects earths atmosphere **Terrestrial energy:** the energy emitted by the earth, almost all the energy emitted comes from the solar energy absorbed by earths surface. This terrestrial energy us absorbed by atmospheric trace gases in the atmosphere (such as water vapor, carbon dioxide and other gases) **Reflected solar energy:** the part solar energy reflected by earths surface. This reflected energy is absorbed, scattered or transmitted by the atmosphere **Atmospheric circulation:** is driven by the energy exchanges within the atmosphere as well as the energy gained and lost across its interface with land and ocean through physical, geological and biological processes organized in earths cycle. The atmospheric circulation is responsible for distributing matter and energy globally and establishing weather and climate patterns. **seminar** Temple skills -- time S skills -- space Novel -- new and original **Lecture 9 -- oct 4^th^** **Module 2 (renewable and non-renewable resources)** Documentary -- Anthropocene