MYP5 Climate Change PDF

What are the consequences of our inactions in response to Climate Change? Unit 6  Key Concept: Global Interaction Related Concept: Causality, Patterns and Trends Global Context: Globalisation and Sustainability Sustainable Development Goal...

What are the consequences of our inactions in response to Climate Change? Unit 6  Key Concept: Global Interaction Related Concept: Causality, Patterns and Trends Global Context: Globalisation and Sustainability Sustainable Development Goals: SDG 7: Affordable and Clean Energy, SDG 13: Climate Action. Statement of Inquiry ‘Both the Causes and Consequences of Climate Change are Global in Scope. We must Ensure that we Manage the Change Sustainably ‘ Inquiry questions Factual: ○ What are the main layers of the Earth's atmosphere? ○ What is the energy budget? ○ What are greenhouse gases and why are they important to the world's climate? Conceptual: ○ what patterns and trends give evidence for global climate change? ○ What natural causes are there for climate change? ○ What are the main human causes of climate change? ○ What are the consequences of climate change? Debatable: ○ Can we manage global climate change consequences? In this Unit we wil…. Find out the causes and consequences of global climate change. Explore examples of how different parts of the world respond to the consequences of climate change.. Take action by finding out ways to promote sustainable responses to global climate change. ATL SKILLS: Communication Skills Critical Thinking Skills Collaborative Thinking Skills Creative Thinking Skills Information Literacy Skills ACTIVITY: 3-2-1 BRIDGE Causes of climate change Individually, write down: ○ 3 thoughts ○ 2 questions ○ 1 analogy... about the causes of global climate change. What do you already know about it? What questions do you have? What does this make you think of, or remind you of? Once you have done this, share your ideas with the class. Do you have the same or different ideas from each other? You will repeat this activity at the end of the section to see how your understanding of the causes has changed. Possible response:3-2-1 BRIDGE 3 Thoughts: 1. Burning fossil fuels like coal, oil, and gas releases large amounts of carbon dioxide (CO ₂) into the atmosphere, trapping heat and contributing to global warming. 2. Deforestation reduces the number of trees that can absorb CO ₂, accelerating the greenhouse effect. 3. Industrial activities and agriculture produce greenhouse gases like methane and nitrous oxide, further contributing to climate change. 2 Questions: 4. How much of climate change is influenced by natural cycles versus human activity? 5. What role do individual actions play in reducing greenhouse gas emissions compared to larger, systemic changes? 1 Analogy: "Climate change is like a thickening blanket over the Earth—every layer added by greenhouse gases traps more heat, making it harder for the planet to cool down naturally." SEE-THINK-WONDER Look at the photos about climate change on the right. What do you see? What do you think about what you see? What does it make you wonder?  You can't have missed the reports in the media about climate change, and the argument that the changes we are observing are too great and too rapid to be attributed to natural causes alone. In this chapter, We will be exploring the characteristics of climate change and the causes that are due to natural processes and human activities. We will investigate the patterns and trends that have led scientists to conclude that climate change is happening because of the activities of humans. We will also focus on some of the consequences of the rapid increase in the global temperature that are already happening, and others that could still happen - and how we can respond to this increase. What are the main layers of the earth Surface? The Earth Atmosphere To understand how the climate is changing we need to understand the nature of the atmosphere and how the atmosphere interacts with the Earth's mass so that the Earth's temperature is regulated. Figure 9.2 shows the layers in the Earth's atmosphere. As the distance from the Earth increases, the density of the atmosphere decreases (the air thins). The lowest and most dense part of the atmosphere is known as the troposphere. Our weather occurs in the lowest layer of the troposphere, while the upper regions of the troposphere, known as the stratosphere is where aeroplanes fly. The Earth Atmosphere The ozone layer is a layer within the stratosphere that is relatively rich in a form of oxygen molecule called ozone 0 3 ; this thin layer is important as it filters out some of the Sun's more energetic, shortwave ultraviolet radiation. The troposphere and stratosphere together extend to about 50 km above the Earth's surface. The temperature across the troposphere and stratosphere steadily decreases from an average of 35 C at the Earth's surface to around -75 C at the outer reaches of the stratosphere, where it becomes known as the mesosphere. This is the region where most meteors burn up, and beyond this are the regions where cosmic rays and particles interact with gas molecules to form aurorae. Layers of the Earth's atmosphere.  EXTENSION: ASIGNMENT Carry out further research into what happens in the other atmosphere layers: mesosphere, thermosphere and exosphere. What happens to the temperature as you go further up into the atmosphere? Atmosphere The atmosphere is a dynamic system. It consists of a variety of transparent gases dominated by nitrogen and oxygen. It is kept in place by the Earth’s gravitational forces. It is something we generally take for granted, perhaps because we can’t really see it as a mix of gases. However, it is absolutely vital for any life to exist, including us. For example: a. it provides a shield from meteorites b. it protects us from the sun's harmful radiation c. it moderates and stabilises our climate, including the temperature d. it supplies us with the oxygen we breathe and plants with the carbon dioxide that they need for photosynthesis. Atmospheric System Most of our atmosphere is located close to the earth’s surface where it is most dense. The air of our planet is 79% nitrogen and just under 21% oxygen; the small amount of the remaining is composed of carbon dioxide and other inert gasses such as argon, neon etc. There are four distinct layers of the earth’s atmosphere. These include Troposphere, stratosphere, mesosphere and thermosphere. Layers of the Atmosphere Source: Randy Russell, UCAR  Troposphere The layer that is most relevant us is the lowest layer: the troposphere. It is the layer closest to the Earth’s surface and includes where we live. It extends up to about 10 km above sea level and is where: a. The Earth's surface absorbs heat from the sun. The warm Earth then heats the atmosphere through conduction. The troposphere is warmest near the Earth's surface with temperature declining by around 6.5 - 7.5°C per km. b. Wind speeds increase with height. The jet stream, which blows powerful winds towards the east, occurs at the top of the troposphere. These air streams are sometimes used by commercial aircraft to reduce flight times. c. Most of the atmospheric mass is found in this layer. It includes nearly all the water vapour, clouds and pollutants. d. Most of our weather occurs in the troposphere. e. Humans and other organisms have most interaction in this layer, for example through the exchange of gases or through the introduction of pollutants. f. The greenhouse effect occurs here and helps to regulate the temperature of the Earth. The tropopause marks the point at which temperatures stop decreasing and is the top of the troposphere. Stratosphere The stratosphere layer extends from 10 Fig. 3: Ozone layer in the stratosphere to 50 km above sea level and is where: filters the ultraviolet rays from the sun. Stratospheric ozone absorbs ultraviolet (UV) radiation from the sun (Fig.3). Temperature is constant at about –60°C in the lower part of the stratosphere, which is shielded by the ozone layer, but then increases with altitude. The air is dry. Winds increase with height. The stratopause marks the top of the stratosphere and is where the temperature remains constant with Source: Kognity altitude. Mesosphere Thermosphere The mesosphere layer ranges from The thermosphere layer extends beyond about 50 to 80 km and is where: about 80 km to between 500 and 1000 km. In the thermosphere: Without the presence of ozone UV and X-radiation from the sun is or other particulates to absorb absorbed, which breaks molecules UV radiation, the temperature apart into atoms (oxygen, nitrogen declines with height. It is the and helium atoms are the main coldest part of the atmosphere components in the upper thermosphere). with temperatures falling to – The temperature increases with 90°C. height and can reach beyond There are strong winds with 2000°C. This heat can cause the speeds up to around 3000 km/h. layer to expand, causing a variation The mesopause occurs at the top of in depth over time from 500 to 1000 km. the mesosphere and is where the temperature does not change. Ionosphere Figure 4. Northern lights (aurora borealis) in Iceland. The ionosphere is also located within the thermosphere and comprises an area in which the particles are electrically charged. The ability of short-wave radiowaves to bounce off these ions back to Earth is used by amateur radio enthusiasts to communicate over large distances. This is also where aurorae polaris (polar lights consisting of both the northern lights in the northern hemisphere and southern lights in the southern hemisphere) occur as a result of electrically charged particles from the sun colliding with ions in the ionosphere Source: (Getty Images/iStockphoto Energy Budget insolation = incoming solar radiation The atmosphere is an open energy system receiving energy from both the sun and the earth. Incoming radiation from the sun is short wave, outgoing radiation is long wave. The sun's energy drives all weather systems and climates. Most is absorbed in tropical latitudes and redistributed to polar latitudes. Write notes on the Energy Budget Activity: Research the terms: Wavelength, shortwave radiation, longwave radiation, latent heat, conduction. State the meaning of each term and explain how it applies to the Earth's atmosphere. Describe the diagram in Figure 9.4. Analyse the diagram to determine the percentage of the Sun's energy that is lost: ○ to space by reflection ○ through absorption and emission. Describe how the energy lost to space through these two different processes might differ.  Most of the Earth's energy comes from the Sun. The atmospheric temperature is maintained by solar energy. If the Earth absorbed all the incident energy, we would be constantly heating up. However, the Earth's average temperature has not changed much since the last Ice Age, just under 12,000 years ago. For the Earth's temperature to be regulated, and equilibrium maintained, some of the Sun's incident energy must be lost into space. This balance of incident and lost energy is known as the Earth's energy budget. Figure 9.4(Next slides) shows the Earth's energy budget. The amounts of energy are measured in watts per metre-squared (Wm2) Notice that there are two main processes by which energy is lost from the Earth and from the atmosphere: ○ By reflection, or ○ by absorption and emission. Inquiry question What is the difference between Weather and Climate? Is there a difference between Climate change and Global Warming? How can we explain the greenhouse effect? What is enhanced greenhouse effect? Online Resources: NOAA Website - Difference between Weather and Climate Climatekids.NASA- What is Climate change The greenhouse effect TED-ED- Enhanced greenhouse effect What are greenhouse gases? Why are they important? As shown in Figure 9.4, the Earth naturally regulates its temperature by reflecting longwave radiation out and by having gases in the atmosphere that can absorb the shortwave radiation. The layer between the troposphere and the stratosphere known as the ozone layer(03) is particularly important in this respect since it absorbs, and so shields the Earth from, certain kinds of ultraviolet light that have shorter wavelengths. Shorter wavelength radiation tends to carry most energy and can damage biological material - in the extreme, ○ very short wavelength radiation such as x-rays and gamma rays can cause damage to DNA and so lead to cancerous mutations, ○ but even ultraviolet radiation in large enough doses can cause 'burning' - that is, cellular damage  Greenhouse gases are gases that absorb longer wavelength, infrared radiation from the Sun and reflect some back down to the Earth. ○ They are so called because this effect was thought to work in the same way as glass in a greenhouse, which causes solar radiation to be 'trapped' and so warms the air inside the greenhouse. ○ In fact, the atmospheric process of greenhouse warming is far more complex than this. There are many greenhouse gases but the most important ones are carbon dioxide CO2, methane CH4 , water vapour Hp and ozone 03. It is important to realize that without these gases, the Earth's atmosphere would have a very different equilibrium temperature: it would be a whole lot colder on the planet and life would be far less sustainable. This action is known as the natural greenhouse effect; the gases occur naturally and the Earth needs them to trap the heat to maintain life.  Figure 9.5 shows this process, where most of the shortwave solar radiation is absorbed or reflected into space, and the remainder is absorbed by the Earth. This absorbed shortwave radiation transfers energy to the Earth, raising its temperature, and this in turn causes the Earth to re-emit some radiation. However, the back radiation is emitted at a longer wavelength than before, such that it is more likely to be absorbed by greenhouse gases in the atmosphere, again raising their temperature and subsequently being re-emitted once more. Activity: Consider the following scenarios: A decrease in rainfall and therefore less evaporation An increase in forest fires around the globe Catastrophic volcanic activity and therefore ash being released into the atmosphere around the globe Working in small groups, Describe how the different scenarios might affect the energy exchange processes as shown in Figure 9.5. Suggest how they might affect the overall global atmospheric temperature. Discuss your thoughts. Activity: Consider the following scenarios: Of course, different kinds of surface have different properties. Highly reflective surfaces such as snow or ice, or water vapour in the form of clouds, raise the overall amount of solar radiation that is immediately reflected back into space. Conversely, land masses tend to absorb the energy. Human-made surfaces such as asphalt are highly efficient absorbers - as you may have noticed if you have ever seen asphalt roads melt on a hot day. What Patterns and Trends give evidence for Global Climate Change? WHAT MAKES YOU SAY THAT? Analyse Figures 9.6 and 9.7. What's going on? What do you see that makes you say that? Some History The advent of powerful computing systems in the 1960s and 1970s allowed for climate models to be developed which showed that these changes could lead to large-scale, even global shifts in the atmosphere's temperature and in weather systems. The first United Nations conference on the Human Environment or 'Earth Summit' took place in Stockholm, Sweden in 1972, and they now occur every ten years. In 1992, in Rio de Janeiro, Brazil, the United Nations Conference on Environment and Development took place, at which the United Nations Framework Convention on Climate Change (UNFCCC) was launched. Those who signed up to the convention have met every year since 1995. During this period, scientific evidence of patterns and trends over time in temperature, carbon dioxide in the atmosphere, sea levels and other indicators have been analysed. According to NASA, 'Ninety-seven percent of climate scientists agree that climate-warming trends over the past century are very likely due to human activities, and most of the leading scientific organizations worldwide have issued public statements endorsing this position.' 1 https://climate.nasa.gov/evidence/,accessed 17 November 2018 However, some people still believe that climate change is not anthropogenic (caused by humans), but rather is a natural fluctuation in global temperature. What are the Natural Causes of Climate Change? THINK-PAIR-SHARE How do you think the events shown in the three images in Figure 9.8 might affect the Earth's climate? Natural Causes of Climate Change As we have seen, the evidence for the rapid global Group Work: climate change overwhelmingly points to human Investigate the Natural causes. causes below and present to However, some natural occurrences certainly do the class. change the global temperature. Any changes in the atmosphere will result in changes Sunspot in the Earth's energy balance. Changes in the Natural changes in atmosphere are known as forcings (see MYP Sciences Albedo by Concept 3 and 4&5 for more on the scientific Massive Volcanic background for these processes) Natural forcings include sunspot activity, natural Eruption (Global changes in the albedo effect, massive volcanic Dimming) eruptions, ocean currents and natural methane Natural Methane release release. We will be investigating how each of these Ocean Current can naturally change the global climate. What are the main human causes of climate change? How do we know that climate change has been mainly caused by human activity, or what is also known as the enhanced greenhouse effect? Since the Industrial Revolution in Britain and elsewhere, there has been an increase in carbon emissions in the atmosphere. DISCUSS Compare and contrast the two graphs in Figures 9.12 and 9.13. What correlations do you observe? What might you deduce? Explanation for the relationship The two graphs in Figures 9.12 and 9.13 suggest that there is a correlation between the amount of carbon emission and the increase in the Earth's temperature. While a correlation does not necessarily prove a causal connection, science does show that increased carbon dioxide in the atmosphere results in increased absorption and retention of energy from longwave radiation. We have seen that there are natural cycles and events that can change the temperature. However, these changes have increased dramatically in the last two centuries.  The increase in greenhouse gases is in many ways due to an increase in wealth; it reflects an increase in consumer goods, the production of which leads to carbon emissions. Examples include mobile devices, and products that themselves directly contribute to the production of carbon, such as vehicles (and a more global society requires more transportation). Figures 9.14 and 9.15 show world maps for carbon dioxide emissions and Gross National Product (GNP) per capita. GDP VS CO2 EMISSIONS Relationship between GDP AND CLIMATE CHANGE As you can see, not all countries with a high GNP have high greenhouse emissions. Some countries have invested in green energy, such as wind power, which lowers their greenhouse gases emissions. Others - such as France - rely on other low-carbon energy resources such as nuclear power. However, an increase in wealth usually means an increase in greenhouse emissions. Around 1750, at the start of the Industrial Revolution, the burning of coal and then other fossil fuels increased. Then the development of the combustion engine increased the release of greenhouse gases into the atmosphere. The number of factories that burnt coal, gas and oil or that used energy that was produced using fossil fuels, continually increased. As nations become wealthier, we tend to see an increase in the number of cities. Another problem has been the increase in consumption of protein in the form of meat which in turn increases the amount of deforestation as land is sought to rear livestock. Goods being shipped have increased, and this again leads to more greenhouse gases. What are the Consequences of Climate change? Use a table, a Venn diagram or another visual organizer. Classify the newspaper headlines in Figure 9.16, and other headlines from around the world from your own research into the impacts of climate change, into the following categories - consequences that: affect both high-and low-income countries affect the oceans and ice (hydrosphere and cryosphere) affect the land (biosphere) affect the atmosphere have affected people (social) affect the economy affect just the environment affect governments(politics). Key Terms Biosphere: it is the part of the earth where life exists, up to a few kilometres into the atmosphere and deep into the earth’s crust or oceans. It is the part where living organisms exist. Hydrosphere: it consists of the total amount of water on the earth, including underground water (groundwater, wells and aquifers), surface water (rivers, lakes and oceans, glaciers, icecaps) as well as water in the air (water vapour, clouds). Atmosphere: it consists of a mixture of solids, liquids and gases that are held to the earth by gravitational force. Cryosphere: refers to the part of the the earth that is frozen – ice sheets, glaciers etc, most of which are in the Arctic and Antarctica What are the Evidence of Climate Change? 1. Rising Global Temperatures: Not Just a Hot Day! 2. Melting Glaciers and Polar Ice: 3. Rising Sea Levels: Why Coastal Cities are at Risk 4. More Frequent Extreme Weather Events CONSEQUENCES FOR THE CRYOSPHERE AND THE HYDROSPHERE Melting of Ice: Rise in Sea Level We all know what happens to ice when it heats up. Water has an unusual property, however: it is one of the very few substances whose solid state (ice) occupies a greater volume than its liquid state. This means that when ice melts, it actually reduces the volume occupied. This is why icebergs float on water - they are less dense than the water around them. Consequently, melting sea ice will not raise sea levels globally. However, the vast majority of surface ice is in the form of snow and ice that is currently lying on land. If this ice melts, the water will run into the oceans and result in an increase in sea level globally. Animation: How Glaciers melt Impact on Cryosphere Oceans (acidification): evidence & As atmospheric CO2 increases, more carbon Hydrosphere dioxide is dissolved in seawater. This results in the creation of carbonic acid and a decrease in pH as the oceans become more acidic. As many creatures in the sea have shells made from calcium carbonate, this increase in acidity has a detrimental effect on the development of their shells. Many crustacean species have declined in recent years. Marine food webs are affected by the crustacean population decreasing, and this has an impact on fishing regions. Coral bleaching also occurs, as the coral cannot develop its skeleton, and again this has a negative impact on sea life in coral regions.  Impact on Cryosphere & Hydrosphere Carbon stored in ice: permafrost melting As the global temperature is increasing, the permafrost regions are starting to melt. As the ice thaws, methane that has been trapped underground for millions of years has started to leak out. As we saw earlier, this results in a positive feedback loop in the global warming process. Consequences Of Climate change on the Biosphere: Global spatial changes in biomes and habitats The biosphere encompasses the areas of the globe where life occurs - whether on the Earth's surface or in the air. Global temperature increase has had a wide impact on the biosphere, and on living conditions. Some might even say that the consequences are not all bad. ○ One of the many effects that have been observed as a result of climate change is that the locations of certain biomes have changed. ○ One example is the mountain biomes. Many glaciers in mountainous regions have reduced in size; this has had an effect on flora and fauna in these ecosystems. Consequences Of Climate change on the Biosphere: Global spatial changes in biomes and habitats Some species of plant have dropped in number due to competition from other plant species that can now live in higher altitudes due to the warmer climate. (See http://sciencenordic.com/climate-change-altersmountain- plants for an example of research that has shown that some high-altitude plants in the Alps have declined in number.) With the change in plant species comes a change in animal species and numbers. ○ In the tropical regions of the world, warming can bring an increase in the number of insects, such as the mosquito. ○ It has been observed that in specific elevations the number of mosquitoes has increased, and in certain parts of these areas, tropical diseases such as malaria have increased. Global spatial changes to agriculture Climate change and human activity can work together to increase the impact on the land. One of the most significant areas that have been affected by climate change is the Sahel in sub-Saharan Africa. With the temperature increase and issues of overgrazing and cultivation, the land has become desertified. With an ever-increasing population and the associated needs for more resources such as fuel and food, more and more land is exposed to the warmer and drier climate, which in turn leads to further desertification. In other parts of the world, climate change has changed the nature of farming. New crops have taken over from older ones; yields grow as there is a longer growing season, which seems to be a positive consequence. However, this change also impacts on animal life in these regions and therefore the food chain. Some farms might benefit from this change, while others might lose their livelihood. CONSEQUENCES THAT AFFECT THE ATMOSPHERE Incidence and severity of extreme weather events In 2018 there were many extreme weather events, from forest fires in California, to a heat wave in Europe,drought in Australia,flooding in Bangladesh, and an increase and intensity of tropical cyclones. Figure 9.22 shows the number and intensity of hurricanes around the globe. The image is from an American website, and therefore the term 'hurricane' is used. However,these storms are not called hurricanes in all parts of the world. In the North Pacific, they are known as typhoons; in the Atlantic, they are known as hurricanes, and in and around the Indian Ocean, they are known as cyclones. They are, however,all the same: a reason f very low pressure with high winds and heavy rain that develop over warm ocean regions.  Over the years, the number and intensity of these weather events have increased. It is believed that with an increase in atmospheric temperature, the temperature of the upper part of the ocean is also increasing. This leads to an increase in levels of evaporation and therefore lower air pressure. These effects in turn mean more torrential rainfall and higher winds. The impact of these more frequent and intense storms has been devastating in many coastal communities. Global spatial changes to agriculture(2) Source: How Will Climate Change Impact Agriculture? - Youtube/ Source: Agrivi.com Rutgers Climate Institute Drought In 2018, regions such as Australia, California and Europe experienced one of the hottest summers on record. Drought, heatwaves and forest fires dominated headlines in many high-income countries. Can we manage Global Climate change Consequences? Figure 9.23(Next slides) Ways of mitigating and adapting to the effects of climate change: (a) vertical gardens in Paris, (b) houses on stilts in Bangladesh, (c) solar panels and wind turbines, (d) flood defences in the Netherlands and the UK, (e) carbon capture  Now that you have established the difference between mitigation and adaptation, we can start to focus on how the two methods can be used as a response to climate change consequences. Mitigation methods tend to be led by governments. Mitigation tries to reduce the number of greenhouse gases released into the atmosphere. Inter governmental groups, such as the United Nations Framework Convention on Climate Change( UNFCCC), have produced several climate change agreements. The first Earth summit conference was in Rio in 1992. The focus of the convention was to advocate and support mitigation methods However, in 2015 during the UN Paris agreement, the focus shifted to how countries can adapt to the impacts of climate change. Many low-income countries (LICs) need help to adapt to - and become more resilient in the face of - climate change, and the UNFCCC is there to support these governments  Many countries have signed up to help reduce global warming and to help others adapt to the impacts of global warming. However, there are still many people who do not believe that climate change is happening. Figure 9.24 : For us to slow the pace of the impact of An infographic showing the climate change and global warming, main outcomes and some ways of achieving these governments and civil society must outcomes from the UN respond together. Paris agreement in 2015. But, how can this be done while there These are a mixture of mitigation and adaptation are people who deny that it is methods happening? Summative Assignment