Unit 2 Global Climate - Vulnerability and Resilience

Question 1

Describe the structure of the Earth’s atmosphere.

Answer 1

78% NO2, 21% O2, 0.9% Argon, 0.04% CO2
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Thermosphere >80km, a virtual vacuum, rise in absorbed energy and temperatures due to energised short-wave radiation.
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Mesosphere >48km, temperatures decrease with height due to decreasing particle density.
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Stratosphere >17km, lacks dust and water, stable, thin, increase in temperature due to absorption of solar radiation, ozone layer.
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Troposphere >0km, most weather processes take place, fall in temperature as atmosphere thins.

Question 2

What is atmospheric energy balance? And energy budget?

Answer 2

Under natural conditions, energy balance is maintained through radiation, convection, and conduction. About 46% of insolation reaches Earth’s surface; the rest is scattered or reflected, mainly by clouds, gases, and Earth’s albedo.
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Budget describes the balance between incoming energy from the Sun and outgoing energy from the Earth.

Question 3

Describe the difference between short-wave and long-wave radiation in the atmosphere.

Answer 3

A cloudless night means there is a large loss of long-wave radiation from earth, less greenhouse effect.

Question 4

What is the greenhouse effect? Describe the gasses involved in the process.

Answer 4

Water vapor makes up 95% of greenhouse gases by volume and contributes half of the natural greenhouse effect.
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Human activities, like burning fossil fuels and deforestation, increase carbon dioxide levels, which have risen from 315 ppm in 1950 are expected to reach 600 ppm by 2050.
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Methane, largely from cattle, rice fields, and melting permafrost, contributes heavily to warming, increasing by 1% annually.
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Synthetic chemicals like chlorofluorocarbons (CFCs), used in various industrial applications, trap heat more effectively than CO₂ and also harm the ozone layer, with their atmospheric levels increasing at 6% per year.

Question 5

What causes changes in solar radiation on earth?

Answer 5

Changes in atmospheric composition increase global temperatures by disrupting the Earth’s energy balance. Additionally, shifts in reflectivity (albedo) affect climate: as ice melts, darker surfaces like vegetation absorb more solar radiation, further raising temperatures.
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Global dimming, caused by air pollution, reflects sunlight away from Earth, reducing solar energy reaching the surface. Following 9/11, the grounding of flights in the U.S. led to a 1.1°C temperature rise, highlighting this cooling effect. Polluted clouds, with many smaller droplets, reflect more sunlight than natural clouds, potentially masking the full extent of global warming.

Question 6

What feedback loops are present in the atmosphere?

Answer 6

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Positive feedback
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It is believed that global warming is most evident in tundra regions. Most notable in winter warming. Melting ice means less white ice lowering planetary albedo, increasing absorbed energy, leading to further ice melt.
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Rotting vegetation in permafrost releases methane unable to escape due to ice cover. Permafrost thawing will cause methane release furthering enhanced greenhouse effect.
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Increased forest cover in high latitudes decreasing albedo.
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Negative feedback
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Increased evaporation in low altitudes may mean more precipitation leading to increased snow fall on polar icecaps reducing mean temperatures. Growth of Boyabreen Glacier in Norway.
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Increase in carbon, increase in plant growth, increase in photosynthesis.
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Since 2002, Greenland’s ice sheet has increasingly melted, raising sea levels and possibly altering the Gulf Stream. This change could lead to colder winters in Britain, with snow lasting longer, similar to Canada’s colder eastern coast at the same latitude.

Question 7

What is the enhanced greenhouse effect?

Answer 7

This is largely linked to growth in industrialisation, trade and globalisation.

Question 8

What are some implications of climate change?

Answer 8

Increased storm activity and intensity, especially tropical storms.
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Change in agricultural patterns. Growth of vineyards in the UK.
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Less rainfall over US and S.EU leading to possible droughts.
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40% of wildlife species are expected to become extinct.
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Skiing facilities in Scotland such as Aviemore would be forced to shut.
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Wetlands and inland marshes at risk of drying up, threatening birds such as Dunlin.
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Daffodils and Crocuses would only grow in the north of England.
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However, great uncertainty in geography. Exact implications are unknown.

Question 9

What changes can be expected in the hydrosphere? Sea ice?

Answer 9

Increase in melting glaciers threaten 4 million sqr km, 5% of the worlds population, more floods.
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Rising sea levels threaten Venice, where frequent flooding damages historic buildings and disrupts daily life. In response, the MOSE project, a system of retractable flood barriers, was developed to protect the city from high tides and storm surges.
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Arctic sea ice decreased dramatically since 1975. Melting season has increased by nearly 3 weeks since 1979.
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Receding ice means more wave formation, meaning further ice break. Means methane release. Wetter summers in northern Europe due to weakened gulf stream.
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Correlation to extreme weather in northern mid-latitudes.
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Less time for Polar bears to hunt seal pups. Less nutritious and reduced body size with decreased reproductivity.
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Increase in trade routes through previously frozen spaces.

Question 10

What is happening to glaciers and ice caps? Swiss glacier case study.

Answer 10

Source of many of Asia’s major river systems used for drinking, irrigation, industry and power. 2 billion people.
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Population growth and groundwater depletion can also have effects.
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Swiss glaciers, including the Gorner Glacier, are retreating rapidly, largely due to global warming. Since 1850, the glaciated surface of the Swiss Alps has decreased by a third, from 1,800 km² to 1,200 km², reducing total land area coverage from 4.4% to 3.15%. The Gorner Glacier, once 15 km long in 1882, has since receded continuously, shrinking by over 2.5 km. Major retreats occurred in 1950 and 2007–8, with annual losses now averaging tens of meters. This glacial recession threatens water balance, increases the risk of glacial lake outbursts, mudslides, and has significant economic, social, and environmental impacts.

Question 11

What changes will occur in carbon stores? (Oceans, biosphere and ice)

Answer 11

Most carbon is in rocks, unavailable in the natural carbon cycle. 2% of the rest of the carbon is in atmosphere, 5% in biomass, 8% in fossil fuels, and 85% in oceans.

Oceans
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Significant carbon stores, 38,000–40,000 Pg of carbon, 50 x the atmospheres 766 Pg. Climate change is increasing carbon levels leading to ocean acidification that threatens marine life. Since 1750, ocean acidity has risen by 30%, harming shell-building organisms and potentially reducing phytoplankton abundance, despite some growth stimulation.
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Acidification and rising sea temperatures have also caused coral bleaching, diverse sea habitat destruction.
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Biosphere
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Terrestrial plants absorb 1/4 of human carbon dioxide, with growth potentially increasing by 12–76% if carbon levels double. Agriculture impacts the carbon cycle variably; abandoned farmland can revert to forest, conversely, using fire for new farmland releases significant carbon.
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Deforestation and modern farming practices also contribute to carbon emissions, as soils store 75% of land-based carbon.
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Ice
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Periglacial areas, characterized by permafrost, store significant carbon deposits due to low decomposition rates of organic matter, containing 400–500 gigatonnes (Gt) of carbon.
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Thawing permafrost from global warming may enhance primary productivity and nutrient release, but also increase methane emissions, currently at 25–40 megatonnes (Mt) annually. A 4°C temperature rise could boost emissions by 45–65%. Changes in snow cover and permafrost could amplify warming through feedback mechanisms, potentially raising temperatures further if significant thawing occurs.

Question 12

What changes will occur to biomes and agriculture as a result of climate change?

Destruction of forests in the USA case study

Answer 12

Rapid temperature increases limit species’ ability to adapt, with many unable to migrate to suitable habitats, resulting in extinction.
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Reduced biodiversity is expected, particularly among high-altitude and high-latitude species, with models predicting that up to 40% of wildlife could become extinct if temperature rises by 2°C, affecting agriculture and ecosystem stability.
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Forest fires in America
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Dense American forests absorb approximately 13% of the U.S.’s greenhouse gas emissions but face increasing threats from climate change, including wildfires, insect infestations, and drought.
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In 2015, over 10 million acres were burned, the largest area since 1960. Wildfires are a global issue, with record fires in Siberia, Canada, and Indonesia.
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Climate change intensifies drought and extends fire seasons, while warmer weather promotes insect population surges, further stressing forests. The U.S. Forest Service warns that by 2036, American forests may become carbon sources due to these escalating challenges, hindering regeneration efforts
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Mass clearance of dead trees and planting of new trees would be required for mitigation. 1/2 of the USFS budges was spent on firefighting, limiting prevention efforts. However, a warmer climate could enable tree migration to higher altitudes.
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Ponderosa pine, for instance, may move uphill, but its ability to adapt may be hindered by various ecological factors and rapid warming.
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Agriculture
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Rising global temperatures will significantly alter agricultural patterns, potentially reducing crop yields by 35% in Africa and the Middle East with a 3°C increase.
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This could expose up to 550 million people to hunger, shift growing areas poleward, and necessitate crop type changes due to varying water resources.

Question 13

What impacts can climate change have on people and places?

Answer 13

Residents of low-lying islands such as Kiribati in the South Pacific have abandoned their homes, while others, such as in Kivalina, Alaska, are expecting to leave before long.
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Opening up of sea routes as
sea ice melts, such the North-West
Passage connecting the Atlantic Ocean and the Pacific Ocean via the
Arctic Ocean north of Canada.
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Tourism. Extension of summer season and coastal resorts, including opening of more resorts northwards. Less winter sports facilities.
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Social issues
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Possibilities of hunger and conflict limiting economic development.
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LICs will be more impacted with lack of available tech and money. Bangladesh. 20% of GDP and 65% of workforce is in agriculture threatened by floods in low areas.
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When protecting countries from flooding, like the Netherlands, this could lead to, economic and social stress due to loss of land and resources.

Question 14

What extreme weather events are likely to happen as an implication of climate change?

Answer 14

200m at risk of being driven from their homes by flood or drought by 2050.
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Increase in storm activity.
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Reduced rainfall over US and S.EU causing drought.
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4 billion in water shortage if temps rise by 2°C.

Question 15

What are the general impacts of temperature increase at 1, 2 and 4 degrees Celsius?

Answer 15

Up to 1°C Increase

Essential for the survival of low-lying island states, but virtually impossible to achieve.
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Arctic sea ice will disappear in summer; heatwaves and forest fires will increase in subtropical regions.
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Coral reefs, including the Great Barrier Reef, will die, and climate-related diseases will affect 300,000 people annually.
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Up to 2°C Increase
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Annual heatwaves will occur, with summer temperatures in southern England reaching 40°C.
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Amazon rainforest will convert to desert, while ocean acidification will threaten marine life and coral reefs.
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Agricultural yields decline, exposing half a billion people to starvation,
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West Antarctic and Greenland ice sheets will begin to melt, raising sea levels significantly.
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Up to 4°C Increase
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Arctic permafrost will release significant methane and carbon dioxide, accelerating climate change.
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Permanent ice loss in the Arctic will lead to extinction of polar bears and other ice-dependent species.
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Many regions, including Italy and Greece, will become deserts, while southern England will resemble modern southern Morocco.

Question 16

What impacts will climate change have on the UK?

Answer 16

1. Rising temps of about 0.2°C per decade.
2. Increased rainfall (and intensity) and wind speeds by 10% by 2050s.
3. Droughts and floods likely to become more exaggerated.
4. Rising sea levels and higher tides at 5cm per decade.
5. Potential storm surges that could cost up to £200 billion.

Question 17

What disparities are the with climate change?

Answer 17

Vulnerability to its effects is influenced by three main factors: exposure, sensitivity, and adaptive capacity.
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Certain groups, including the young, elderly, disabled, poor, and indigenous populations, face heightened vulnerability due to socio-economic challenges and environmental conditions.
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Low-lying islands, such as those in the Indian and Pacific Oceans, are particularly at risk from rising sea levels, leading to coastal erosion, saline intrusion, and loss of income.
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For example, an 80 cm rise could inundate 66% of Kiribati. Indigenous communities, like the Inuit in Canada, are also impacted, facing changes in their ecosystems that threaten traditional livelihoods. With rising temperatures melting permafrost, their cultural heritage is at risk as they may need to abandon traditional practices for urban employment.
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Overall, climate change exacerbates existing inequalities and threatens diverse communities and ecosystems worldwide.

Question 18

What effects has Bangladesh experienced with climate change? (case study)

Question 19

What effects has Switzerland experienced with climate change? (case study)

Question 20

What examples of government-led action on climate change is there?

Answer 20

Major fossil fuel countries hinder global climate agreements despite international efforts through organizations like the IPCC and UNFCCC.

UN Framework Convention on Climate Change (UNFCCC)
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Since the 1992 Rio de Janeiro Earth Summit, it aims to stabilize GHG concentrations to prevent dangerous climate interference.
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Since 1994, it struggled to curb emissions, leading to the 1997 Kyoto Protocol, which mandated a 20% emissions cut for high-income countries by 2012, while LICs faced no targets. The USA did not sign, citing concerns over China’s competitiveness.
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Urged HICs to spearhead climate mitigation due to their technological capacity, financial ability, and significant historical emissions, allowing low-income countries time to develop.
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Kyoto Protocol
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Signed in 1997 by 183 countries, aimed to stabilize greenhouse gas emissions to avoid serious climate change, targeting a 5% reduction from 1990 levels by 2012.
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Effective from 2005 and extended to 2015, it established a carbon market allowing countries to trade emission units. The Conference of Parties (COP) oversees the protocol, promoting energy sources that do not emit greenhouse gases, like hydroelectric, solar, and wind power.
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While some countries have turned to nuclear power for clean energy, concerns about radioactive waste and disasters like Fukushima have raised controversy. Success hinges on governmental commitment to international agreements and proactive measures.
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Paris agreement
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From 2015 UN Climate Change Conference, signed by 174 countries, aiming to limit global warming to 2°C above pre-industrial levels. It targets zero net anthropogenic greenhouse gas emissions by 2050–2100, with a more ambitious 1.5°C goal necessitating zero net emissions by 2030–2050.
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Unlike the Kyoto Protocol, the Paris Agreement lacks country-specific goals and enforcement mechanisms, relying on countries to reduce carbon usage “as soon as possible.” Both the USA and China agreed to limit their greenhouse gas emissions.

Question 21

What strategies are there for mitigating climate change?

Answer 21

Here’s an explanation of each climate change mitigation strategy:

Pollution Management and Control
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Limit pollutants, especially greenhouse gasses.
- Setting emission standards
- Improving waste management
- Controlling industrial processes
Governments and industries use policies and technology to reduce the pollutants released into the air, water, and soil.
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Reduction of Energy Consumption
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Reducing overall energy.
- Efficiency improvements
- Energy-saving technologies
- Energy conservation behaviour
This includes insulation in buildings, using efficient appliances, and adopting smart energy management systems to reduce energy waste.
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Reducing Emissions of Nitrogen Oxides and Methane from Agriculture
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Targets emissions from livestock, fertilizers, and soil management.
- Nitrification inhibitors in fertilizers
- Improving livestock diets
- Sustainable farming practices.
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Using Alternatives to Fossil Fuels
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Switching to renewable energy sources such as solar, wind, hydro, geothermal, and bioenergy instead of coal, oil, and natural gas.
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Renewables produce little to no emissions and are considered a core component of a low-carbon future.
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Geo-Engineering
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Includes large-scale technologies and techniques intended to modify the Earth’s climate.
- Solar radiation management
- Injecting aerosols in atmosphere
- Reflect sunlight
- Direct air capture
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The UN-REDD Programme
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United Nations Programme on Reducing Emissions from Deforestation and Forest Degradation (UN-REDD) supports developing countries to reduce emissions from deforestation and forest degradation.
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It incentivizes forest conservation, sustainable management, and forest restoration to prevent carbon loss.
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Carbon Capture and Sequestration
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Captures CO₂ emissions from industrial sources and power plants, preventing them from entering the atmosphere.
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The captured CO₂ is then transported and stored underground or under the sea, effectively locking it away from the atmosphere.
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Ocean Fertilization
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Involves adding nutrients (like iron) to ocean waters to stimulate the growth of phytoplankton, which absorb carbon dioxide.
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This approach aims to enhance the ocean’s capacity to store carbon, though it’s still experimental and controversial due to ecological risks.
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Carbon Taxes
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Impose fees on the carbon content of fossil fuels, essentially making it more expensive to emit greenhouse gases.
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By increasing costs for high-emission activities, carbon taxes aim to reduce fossil fuel use and encourage cleaner alternatives.
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Carbon Trading
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Companies are given a limited number of carbon emission credits. Those who emit less can sell their unused credits to others who exceed their limits, creating a financial incentive for emissions reductions.
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Carbon Offset Schemes
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Allows companies or individuals to compensate for their emissions by funding projects that reduce or remove emissions elsewhere.
- Reforestation
- Renewable energy projects
- Methane capture
The goal is to achieve “net zero” emissions by balancing emissions with offsets.

Question 22

What are adaptation strategies? What can they involve?

Answer 22

Adaptation strategies, such as flood defences, vaccination programs, desalination plants, and climate-resilient crops, can help reduce negative impacts. HICs can support MICs and LICs with financial and technological resources.
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Cities will need defences against rising sea levels, and widespread vaccination will be necessary as diseases spread to new areas due to warmer temperatures.

Question 23

What civil society and corporate strategies are there? Case study action taken by non-governmental stakeholders.

Answer 23

The WWF advocates for reduced greenhouse gas emissions, urging governments to adopt renewable energy, conserve forests, and cut aviation emissions. Its UK division introduced the “1 in 5 Challenge,” encouraging companies to reduce flights by 20%, benefiting the environment and organizations through cost savings, productivity gains, and improved work-life balance.
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Vodafone participated by implementing video-conferencing, reducing its flights by nearly 4,000 in one year, cutting 617 tonnes of CO₂ emissions, and saving travel costs.
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These initiatives demonstrate how civil society and corporate strategies can align to address climate challenges effectively and sustainably.
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By 2016, the USA improved its climate performance ranking from 54th to 34th due to corporate and state-level climate efforts.
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Companies and states like California, Florida, and New York set ambitious goals to reduce greenhouse gas emissions by 80% from 1990 levels by 2050.
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Major corporations, including those outside the renewable energy sector, are also committed to CO₂ reduction. Groups like the US Climate Action Partnership (USCAP, 28 companies from 2007, including Chrysler, GE and GM) and Business for Innovative Climate and Energy Policy (BICEP including Nike, Levi, Starbucks from 2008) advocate and invest for emission cuts of 25% before 1990 levels, carbon capture, and renewable energy.
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However, corporate opposition remains, with some lobbying against measures they believe could harm U.S. competitiveness.