L1. Introduction to Climate Change Mitigation (updated) PDF

Climate Change Mitigation BIOS3103 Week 20 31/01/2023 BIOS3103 Kamal Alskaf Outline ❑Why is the climate changing? ❑Impacts of climate change ❑Responses to Climate Change What is Climate changing? Climate change refers to long-term shifts in temperatures and weather patterns. What is Climate...

Climate Change Mitigation BIOS3103 Week 20 31/01/2023 BIOS3103 Kamal Alskaf Outline ❑Why is the climate changing? ❑Impacts of climate change ❑Responses to Climate Change What is Climate changing? Climate change refers to long-term shifts in temperatures and weather patterns. What is Climate changing? Climate change refers to long-term shifts in temperatures and weather patterns. • Natural 1. 2. 3. 4. 5. Plate tectonics (tectonic motion) The sun The earth’s orbit Unforced variability Greenhouse gases • Human activities • Primarily burning fossil fuels like coal, oil and gas. Tectonic motion The earths continents are moving slowly. Over millions of years, this plate tectonics can alter the arrangements of the earth through few technics 1- The location of continents determines whether ice sheets form. 2- Ice sheets matter to the climate because ice reflects sunlight, so the formation of an ice sheet increases planetary albedo, thereby increasing the reflection of solar radiation back to space and cooling the planet. 3- The location of the continents determines the ocean circulation. Example - Drake Passage Happened 30 million years ago when the Antarctic Peninsula separated from the southern tip of South America, thereby opening the Drake Passage. Allowed winds and water to flow around Antarctica. This flow reduced the transport of warmwater and air from the tropics to the South Polar region, causing a dramatic cooling of the Antarctic and contributing to the formation of the Antarctic ice sheet. Pacific ocean Atlantic ocean An energy balance? Incoming solar radiation (energy) … no change Outgoing terrestrial radiation (energy) If GHGs increase … … this decreases Internal energy ≈ T Implications of increase in T? E = σT 4 Incoming = Outgoing + change of internal energy (a decrease here) (so an increase here) The Sun The sun is getting brighter over time as the Sun is burning hydrogen and produced helium, the rate of fusion in the Sun has increased as the build-up of helium leads to increases in the density of the Sun’s core. The stratosphere temperature is not changing so it is unlikely for the Sun to be the main reason for the climate change. The Earth’s orbit The solar constant is determined not just by the energy emitted by the Sun, but also by the Earth–Sun distance. The Earth’s orbit is not a perfect circle: it is an ellipse whose eccentricity – the ratio of the length of the ellipse to the width – varies with time. Snowball Earth A deep freeze began around 715 million years ago and lasted for 120 million years. The equator had an average temperature of -20°C, equivalent to modern-day Antarctica. Most life was wiped out, and the creatures that did survive huddled in small pockets of open water, where hot springs continued to bubble up. • Is it catastrophic? • Is it important for evolution? The development of the first animals, and a dramatic flourishing of life known as the Cambrian explosion. We still don’t know everything about that time. Trilobites like these first evolved during the Cambrian Snowball Earth Energy Atmosphere composition? Greenhouse gases Greenhouse gases exist trapping the sun’s heat and raising temperatures. The natural way our planet cools. Necessary to keep earth at a habitable temperature, but too much, might be harmful. Emissions continue to rise. • • • • The Earth is now about 1.1°C warmer than it was in the late 1800s. The last decade (2011-2020) was the warmest on record. Greenhouse gas concentrations are at their highest levels in 2 million years Main emitters: Energy, industry, transport, buildings, agriculture and land use .. Daily max/min temperature in Europe 19672022 Daily maximum temperatures in 2022 were the highest. The minimum daily temperatures were also the highest in 2022; slightly higher than in May 2020. Daily max/min temperature in Europe 19672022 2022 in Europe The temperatures are shown alongside the maximum and minimum for 2017, the warmest year on record for the region. People are experiencing climate change in diverse ways Climate change can affect • • • • Health Ability to grow food Housing Work Vulnerable people to climate impacts, people living in small island nations and other developing countries. Poverty Climate refugees The 17 sustainable development goals of the United Nations Exponential growth. Example: Lily pads - Lake - 40 years - Based on the first few years data, the lake will be covered with the lily pads in thousands of years (if observer used the linear growth). It will be covered with the lily pads in around 39 years. - This is the exponential growth. The cost of climate change. Exponential growth The rate of growth is directly proportional to the present size. F = P(1 + r/100)n • After n years, an initial investment of P will grow to a final value F. What is exponential growth? The message is that you need to address the exponential growth early. CO U N T RY RANK 1 China 2 CO 2 E M I S S I ON S ( TO N S , 2 0 1 6 ) 1 YEAR CHANGE P O P U L AT I ON 2016 PER C A P I TA SHARE OF WO R L D 10,432,751,400 -0.28% 1,414,049,351 7.38 29.18% United States 5,011,686,600 -2.01% 323,015,995 15.52 14.02% 3 India 2,533,638,100 4.71% 1,324,517,249 1.91 7.09% 4 Russia 1,661,899,300 -2.13% 145,275,383 11.44 4.65% 5 Japan 1,239,592,060 -1.21% 127,763,265 9.7 3.47% 6 Germany 775,752,190 1.28% 82,193,768 9.44 2.17% 7 Canada 675,918,610 -1.00% 36,382,944 18.58 1.89% 8 Iran 642,560,030 2.22% 79,563,989 8.08 1.80% 9 South Korea 604,043,830 0.45% 50,983,457 11.85 1.69% 10 Indonesia 530,035,650 6.41% 261,556,381 2.03 1.48% 11 Saudi Arabia 517,079,407 0.92% 32,443,447 15.94 1.45% 12 Brazil 462,994,920 -6.08% 206,163,053 2.25 1.29% 13 Mexico 441,412,750 -2.13% 123,333,376 3.58 1.23% 14 Australia 414,988,700 -0.98% 24,262,712 17.1 1.16% 15 South Africa 390,557,850 -0.49% 56,207,646 6.95 1.09% 16 Turkey 368,122,740 5.25% 79,827,871 4.61 1.03% 17 United Kingdom 367,860,350 -6.38% 66,297,944 5.55 1.03% Change in CO2 Emissions and GDP The factors controlling emissions • Population • Affluence • Technology I = P x A x T Impact Population Affluence (Consumption per person) Technology (Impact/consumptio n). Burundi 9 millions $900 Agriculture/cycling UAE 9 millions $45000 Industry/meat/cars.. The factors controlling emissions • Population • A significant reduction in the actual number of people on the planet. • Affluence • To reduce the world’s consumption of goods and services • Political problem. People equate consumption with well-being. • Ethically problematic. • Technology • The energy intensity: a measure of how much energy it takes to generate a unit of GDP. • The carbon intensity: a measure of how much GHG is emitted to generate a joule of Energy. Affluence (GDP per person) World population Technology Environment I= P x A x T Ecological footprint Disease and hunger Impact Habitat destruction Economic effects Resources use Break Our responses to climate change can be broadly split into three categories Adaptation Responding to the negative impacts of climate change. If climate change causes sea-level rise, an adaptive response to this impact would be to build seawalls or relocate communities away from the encroaching sea. Mitigation Policies that avoid climate change in the first place, thereby preventing impacts such as sea-level rise from occurring. This is accomplished by reducing emissions of greenhouse gases, usually through policies that encourage the transition from fossil fuels to energy sources that do not emit greenhouse gases. Geoengineering The active manipulation of the climate system. Under this approach, people would continue adding greenhouse gases to the atmosphere, but we would intentionally change some other aspect of the climate in order to cancel the warming effects of the greenhouse gases. For example, increasing the albedo of the Earth. Global greenhouse gas emissions by sector Solar energy Two different ways to generate energy from sunlight: 1) Photovoltaic energy - Direct conversion of light into electric power (no fluids). - Solar panels located on houses or buildings (and on satellites and the Space Station). - Certain materials such as silicon generate electricity when exposed to light. 2) Solar thermal energy - Uses mirrors to concentrate sunlight on a working fluid heating it to several hundred degrees Celsius. - This hot fluid is then used to boil water and drive a turbine, which in turn drives a generator that produces electricity. Solar power pros and cons Pros Cons 1. Renewable 2. ​Solar energy can reduce your home’s electricity bill 3. Homes with solar panels installed may improve home value 4. Solar panels have low maintenance costs 5. Solar energy can generate electricity in any climate. 1. Intermittency 2. The area required to generate solar energy. 3. The high initial costs of installing panels 4. Solar energy storage is expensive 5. Solar doesn’t work for every roof type Wind energy Windmills or wind turbines. The Dutch have used them for hundreds of years. Sophisticated technology. In 2020, the largest turbine had a diameter of 160 meter. A wind turbine can generate as much as 10 MW of power every year. Offshore and onshore. Putting upwind turbines does not preclude using the land simultaneously for other activities (agriculture). Wind energy pros and cons Pros Cons • Clean energy source • Intermittent • Renewable energy source • Environmental impact • Space efficient • Noise pollution • Cheap energy • Aesthetics • Limited locations Biomass energy The process of growing crops and then burning them to yield energy. Pros • Renewable Cons • Expensive • Reliable • Requires space • Abundant • Greenhouse gas emissions • Waste reduction • Environmental impact • Carbon-neutral The biomass energy systems are a promising technology, but any biomass systems must be carefully constructed from end to end to ensure that carbon emissions are reduced. Hydroelectricity energy Generated when water running through a dam spins turbines and generates electricity. Source for 16% of the world’s electricity. Limited! • Many of the world’s big rivers are already dammed, and new dams often cause local environmental problems • Opposition from those individuals living in the area. Hydroelectricity energy Pros • Minimal pollution • Clean energy source • Relatively low operations and maintenance costs. • The technology is reliable and proven over time • Renewable - rainfall renews the water in the reservoir, so the fuel is almost always there Cons • High investment costs • Hydrology dependent (precipitation) • Wildlife • Loss or modification of fish habitat • Fish entrainment or passage restriction • Changes in reservoir and stream water quality • Displacement of local populations • Conflicts between countries. Nuclear energy The energy in the nucleus, or core, of an atom. One of the most contentious options for reducing GHG emissions. Nuclear reactors generate 16% of the world electricity. Uranium fuel. How does nuclear power work? • Heat • Steam • Turbines generate electricity. Nuclear energy Opponents 1) Reactor safety a. b. c. Meltdown of a reactor at Chernobyl 1986. Explosion of a reactor in Fukushima Japan in 2011 after a tsunami damaged the plant. Power plants are attractive targets to terrorists. 2) Nuclear waste Geological Disposal Facilities (GDF) to dispose of nuclear waste in many countries. 3) Proliferation - Nuclear weapons – conflicts. The nuclear power plants are relatively cheap to run, they are extraordinary expensive to build Is it renewable energy? Environmental catastrophes around the reactors Total energy supply (TES) by source, UK 1990-2021 4,000,000 Less depending on oil, coal and natural gas. Limited investment in the hydro power. Around 25% of our projected electricity demand in 2050 will be from nuclear power. Total energy supply TJ Increasing in wind and solar energy. 3,500,000 3,000,000 2,500,000 2,000,000 1,500,000 1,000,000 500,000 Coal Natural gas Nuclear 1990 2000 Hydro 2010 Wind, solar, etc. 2021 Biofuels and waste Oil Carbon capture and sequestration (CCS) The process by which fossil fuels are burned in a way that the carbon dioxide generated is not vented to the atmosphere. Rather the carbon dioxide is captured and placed in long term storage. Combination with coal combustion. CCS may be the only way to both burn this coal and avoid climate change. (source: https://energywatch-inc.com/carbon-capture-utilizationstorage-pipe-dream-potential-solution/) Carbon dioxide removal The attempt to modify the carbon cycle in order to remove carbon dioxide from the atmosphere much faster than natural processes. • Planting trees. • Adding iron to the ocean • To remove carbon dioxide from the air chemically. • Attractive because it would stabilise the climate (temperature, ocean acidifications and precipitation). Carbon dioxide removal problems - The scale required of required carbon dioxide removal is enormous. - Humans are adding 40 billion tonnes of carbon dioxide to the atmosphere every year). - Some approaches to removing carbon dioxide from the atmosphere like adding iron to the oceans could be risky. - Uncertainty about the carbon cycle in the oceans (we know that there are too many details which we don’t know. Unforeseen and serious impacts on ocean ecosystems. Solar radiation management. How to increase the Earth albedo Increasing the aerosol in the atmosphere • Inject SO2 into the atmosphere. • SO2 reacts with water vapour to form sulphate aerosols which reflects the sunlight back to space, thereby increasing the albedo of the Earth and leading to cooling. • It is the same mechanism by which volcanic eruptions cool the planet. Increasing the reflectivity of the low clouds. To increase cloudcondensation-nuclei (CCN) into the clouds. Seeds that cloud droplets form around. The advantages of solar radiation management Pros • High confidence, the physics supporting these suggestions is robust. • Once implemented, temperatures will react immediately • Cheaper than building a nuclear reactor. Cons • Solar radiation management may create other problems. • When started, it is difficult to stop. The life-time of aerosol in the atmosphere is a few weeks to a few years • Political problems. Overall solar radiation management is appealing but risky!!! Summary There are natural and human reasons for climate change. Responses to climate change can be roughly divided into three categories: adaptation, mitigation, solar radiation management and carbon dioxide removal. Everyone of them has advantages and disadvantages. Time scale of mitigation. The impact of the mitigation can be seen in decades. This is because of the time required for the emissions to decrease in the atmosphere and then for the temperature to decrease. References Dessler, A.E., 2021. Introduction to modern climate change. Cambridge University Press. Kannan, N. and Vakeesan, D., 2016. Solar energy for future world:-A review. Renewable and Sustainable Energy Reviews, 62, pp.1092-1105. https://doi.org/10.1016/j.rser.2016.05.022 Nadarajah Kannan, Divagar Vakeesan, Solar energy for future world: - A review, Renewable and Sustainable Energy Reviews, Volume 62, 2016, Pages 1092-1105, ISSN 1364-0321, https://doi.org/10.1016/j.rser.2016.05.022. Resources are uploaded on Moodle. Any questions