Unit 2: Global Climate
Global Warming
A gradual increase in the overall temperature of the Earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, CFCs and other pollutants.
Physical Risks
Damage to companies infrastructure caused by climate change-related hazards such as hurricanes CARGILL: Posted low earnings as a result of prolonged drought in the US.
Resilience
The ability of a system to maintain certain functions, processes, or populations after experiencing a disturbance.
Heat Waves Effects on Health
→ 125 million more vulnerable people over the age of 65 years were exposed to heatwaves in 2016 than 2000. → Due to changing climate conditions in countries where dengue is endemic, the capacity for one of the main mosquitoes to transmit dengue fever (and other diseases such as malaria) has increased globally since 1950 by 9.5%.
Energy Balance
→ All gains of incoming energy and all losses of outgoing energy. The plant is approximately in equilibrium, therefore the sum of gains is approximately equal to the sum of losses. → The absorbed solar (shortwave) radiation heats up the Earth, however as the Earth continues to absorb heat radiation it will not continue to heat up. → In response to the heating, the Earth emits longwave radiation into space which cools the Earth's temperature. → As the Earth's temperature cools, it emits less longwave radiation into space but because the Earth absorbs solar radiation it continues to heat up.
List 3 ways rises in sea levels will impact those living in low-lying coastal areas.
→ As seawater reaches farther inland, it can cause destructive erosion, wetland flooding, aquifer and agricultural soil contamination, and lost habitat for fish, birds, and plants. → These low lying coastal areas bear the burden of storm damage with annual losses from flooding in the globe's biggest coastal cities could rise from about $6 billion a year today to $1 trillion a year by 2050. → In addition, half of the globe's population live in coastal areas that will become increasingly vulnerable to flooding. Higher sea levels would force them to abandon their homes and relocate.
Which countries release the least carbon dioxide?
→ Countries in Sub Saharan Africa → Australia
How soil can be managed sustainability
→ Governments need to write policies to preserve the soil. → Urban development could happen vertically rather than sprawl. → Using more sustainable agriculture practices, e.g. crop and livestock rotation, leaving fields fallow (empty), use cover crops (a crop grown for the protection and enrichment of the soil), reduce filling. → Healthy soil is able to absorb carbon dioxide. Restoring soil carbon by 0.4% per year, it could save up to 75% of global annual emissions.
Which countries release the most carbon dioxide?
→ Japan → USA → India → China
Case Study: Swiss Ski Resort
→ Loss of summer skiing as there is no longer any snow in the summer. → 8 out of 10 summer ski resorts have closed since the 1980s (Only remaining ski resorts are Zermatt and Saas Fee). → 70% drop in snow cover by 2100 → 44% of global ski visitors go to Swiss Alps
Natural Sources of Methane
→ Plant and animal remains decompose → Animals emit wind from their anus → Manure decomposes and it is released from swamps, peat bogs, landfills and rice paddies.
Adaptation
Actions taken to counteract new or changing environmental challenges and reduce the vulnerability of human systems to the effects of climate change.
Price Risk
Arise from large changes to the cost of raw materials, which can result from fluctuations in the supply of energy, water and input commodities. IKEA: Uses renewable energy where possible to become self-sufficient power VOLKSWAGEN: Aims to produce all the energy needed for their factories on-site, taking their factories off the wider electricity grid.
Thermal Expansion
As water warms, its molecules move and interact more, causing the water to take up more space. This process is referred to as thermal expansion.
Case Study: Forest Protection in Mexico
Community project to protect forest 19,000 ha of forest, 3400 ha is sustainably forested. This maximises the carbon sequestration. By cutting trees at the right time (35 years from planting), the maximum carbon is caught and allows regeneration of trees before cutting again.
Spatial Changes in Biomes
Different plants and animals due to climate change are moving towards the poles where it is cooler, higher up mountains where it is cooler, or towards the equator where it is wetter.
Global Warming Potential
Global warming potential (GWP) is a relative measure of how much heat a greenhouse gas traps in the atmosphere. It compares the amount of heat trapped by a certain mass of the gas in question to the amount of heat trapped by a similar mass of carbon dioxide.
How does globalisation and externalities impact the enhanced greenhouse effect?
Globalisation has accelerated and amplified the enhanced greenhouse effect. Through externalities such as increased trade, production, and transporting of goods, more greenhouse gases are produced.
Rating Risk
Highest cost of capital because of additional costs due to climate change. EXAMPLE: Carbon pricing, outdated or unethical technology, disrupted supply chains.
Case Study: Inuits in Canada
Impact on Cultural Identity → Climate change is interfering with the Inuit populations whole way of life and identity which is unique and connected to nature and the environment. → Inuits have maintained close relationships to ice, land, sky, and wildlife which are prominent in the Arctic climate that the population resides in. → Inuits rely on innovative survival skills that are adapted to the unique weather and climate of the Arctic. Impact on Traditional Values → Nunavummiut depend on fishing, hunting, and gather to support themselves and the local economy in their communities. Local hunting practices have evolved as new technologies have developed. → Inuit elders traditionally used their skills to predict weather through observing changing wind and cloud patterns. The population's weather and climate-related knowledge do not fit with current weather conditions and patterns. Impact on Food Security → Caribou migration routes are changing, therefore making it more challenging to hunt. → Fish are moving deeper into the ocean which makes it more difficult to catch. → Less access to wildlife and more safety risks with changes in sea ice thickness and distribution, permafrost conditions, and extreme weather events, hence affecting traditional food security. → Changes in water and air currents are bringing contaminants into the Arctic. In addition, changes in ice cover and thawing permafrost appears to have contributed to an increase in mercury levels in some northern lakes, resulting in an increase of food contamination. → Warmer temperatures bring more flies which feed on and contaminate small fruit. Small fruit is needed in the summer. → Food storage is affected by warmer temperatures and thawing permafrost. Elders suggest that outdoor meat caches that used to remain fresh and preserved in the cold, now get spoilt. Impact on Health and Disease → Diseases that can be transmitted from animals to humans (zoonotic disease) are predicted to increase with the rising temperatures. → Previously isolated animal species may come in contact with each other when natural barriers like ice or snow decrease from climate change. → Extreme weather and natural hazards are both direct impacts on human health → Unpredictable weather patterns may cause more accidents and emergency situations. → Search and rescue missions are affected, as searches are often held back by these unpredictable weather patterns. Impacts on Heritage and Special Places → Delayed freezing of sea ice causes coastal erosion → Freeze-thaw cycles promote the decay of artifacts and ancient buildings (sod houses) → Rising sea levels threaten islands → Nunavut has seen more tourists who want to experience our unique Arctic environment and visit heritage sites, parks and special places. However, the increased deterioration negatively impacts tourism. Impacts on Infrastructure → Roads collapsing due to melting permafrost (houses subsiding) → Dangerous to travel across the ice - thin, carcasses, water transport increasingly difficult as water levels are decreasing in some areas. → New sea routes opening up increases risk of oil spills, accidents, other pollution events.
Anthropogenic
It is (chiefly of environmental pollution or pollutants) originating in human activity.
What are the five natural carbon fluxes?
Photosynthesis → In this process, CO2 is removed from the atmosphere and stored in the structure of plants. Plant Respiration → Plants also release CO2 back to the atmosphere through the process of respiration. Literfall → In addition to the death of whole plants, living plants also shed some portion of their leaves, roots and branches each year. This decomposes into the soil. Soil Respiration → When dead organic matter is broken down or decomposed CO2 is released into the atmosphere at an average rate of about 60 PgC/year globally. Ocean-Atmosphere Exchange → Inorganic carbon is absorbed and released at the interface of the ocean's' surface and surrounding air, through the process of diffusion.The formation of carbonate in seawater allows oceans to take up and store a much larger amount of carbon than would be possible if dissolved CO2 remained in that form. Carbonate is also important to a vast number of marine organisms that use this mineral form of carbon to build shells.
What are the positives and negatives of ice melting?
Positives → The decrease in sea ice results in more area for shipping transport routes. It makes transport of produces more efficient . → As sea ice melts, energy and oil companies are able to search further north for untapped resources using a process known as seismic blasting to shoot air explosions into the water to map the ocean floor and find oil. Negatives → For marine species, such as polar bears, walruses, and seals, ice melting will result in the destruction of habitat. → Ocean dwelling animals such as bowhead whales and narwhals are not immune to these environmental changes. → The process of seismic blasting has detrimental impacts to the ecosystem of the Arctic ocean, causing physical trauma and habitat relocation in whales.
External Forcing
Sunspots → It changes the total amount of solar radiation → Increase in magnetic activity resulting in dark spots → It cools down hot gases within → Solar energy decrease by 0.2% during week-long periods Volcanic Eruptions → It can alter the climate of the Earth for short or long periods of time. → Volcanoes affect the climate through the gases and dust particles emitted into the atmosphere during the eruption (sulfur, carbon monoxide, ash). → Volcanic dust and gas may warm or cool the Earth's surface depending on how sunlight interacts with the volcanic material.
What are the four major carbon pools?
The Earth's Crust → The largest amount of carbon on Earth is stored in sedimentary rocks within the planet's crust. The sedimentary rocks on Earth store 100,000,000 PgC (Petagrams of carbon) and 4,000 PgC is stored in the Earth's crust as hydrocarbons. Oceans → The Earth's oceans contain 38,000 PgC, most of which is in the form of dissolved inorganic carbon stored at great depths where it resides for long periods of time. A much smaller amount of carbon, approximately 1,000 Pg, is located near the ocean surface. This carbon exchange with the atmosphere involves physical processes, such as CO2 gas dissolving into the water, and biological processes, such as the growth, death and decay of plankton. Atmosphere → The atmosphere contains approximately 750 PgC, most of which is in the form of CO2, with much smaller amounts of methane (CH4) and various other compounds. Carbon in the atmosphere is of vital importance because of its influence on the greenhouse effect and climate. The relatively small size of the atmospheric carbon pool also makes it more sensitive to disruptions caused by an increase in sources or sinks of carbon from the Earth's other pools. Terrestrial Ecosystem → Terrestrial ecosystems contain carbon in the form of plants, animals, soils and microorganisms (bacteria and fungi). Of these, plants and soils are by far the largest factors when dealing with the entire globe. The Earth's plants store approximately 560 PgC, with the wood in trees being the largest fraction. The total amount of carbon in the world's soils is estimated to be 1500 PgC.
Atmosphere
The atmosphere is a thin layer surrounding the Earth's surface and is composed of four layers.
Geo Engineering
The deliberate, large-scale manipulation of the Earth's atmospheric system to mitigate the impact of anthropogenic climate change.
What does the temperature of the Earth depend on?
The temperature of the Earth depends on the total radiation received from the Sun.
How is the temperature of the Earth determined?
The temperature of the Earth is determined by the amount of longwave radiation emitted into space.
Atmospheric Layers
There are four main layers including the troposphere, stratosphere, mesosphere and thermosphere.
What percentage of the earth is covered in water?
Total water on Earth → Salt water in oceans and salt lakes is 97% → Fresh water is 3% Earth's fresh water → Ice is 76% → Shallow groundwater is 12% → Deep groundwater is 11% → Lakes and rivers are 0.34% → Water vapour is 0.037%
What is the name given for a store of carbon and what is the name given to the movement of carbon between two stores?
When viewing the Earth as a system, these components can be referred to as carbon pools (also called stocks or reservoirs) because they act as storage houses for large amounts of carbon. Any movement of carbon between these reservoirs is called a flux.
Stratosphere
→ 20 to 50 kilometres above sea level. → Concentration of ozone in the stratosphere, which absorbs UV radiation. → Temperature rises with increasing altitude in the stratosphere → Top part of the layer absorbs higher levels of UV radiation and therefore is warmer, around 0C. → The tropopause, which is the intersurface between the troposphere and stratosphere is around -50 C.
Mesosphere
→ 50 to 80 kilometres above sea level. → Coldest layer of the atmosphere, it contains very little cloud, dust, ozone or water vapour to absorb heat energy from the Sun. → It has the strongest winds in the atmosphere with up to 3000 kilometres per hour. → It comprises the mesopause which separates the mesosphere and thermosphere above it, this is at a constant temperature of -90 C.
Tecnosol
→ 75% of rural population are not connected to national grid and have no electricity. → It was established in 1998. → It provides solar power to poorest rural families. → It cover the whole of Nicaragua and expanded into Honduras and El salvador. → 40 000 solar power systems sold helped quarter of a million people, saved 11 million litres of kerosene and 26000 tonnes of carbon dioxide emissions. → It provides electricity in areas too isolated to provided cables to → Electricity allows shops to stay open longer, butchers throw away less meat. People can create a livelihood due to having electricity.
Albedo
→ A measure of how strongly an object reflects light from its light source such as the Sun → Fresh snow has one of the highest albedos, reflecting 95% of the Sun's radiation. → If the climate in an area cools, the surface cover of snow and ice might expand over grassland or bare earth, and this will increase the area's albedo because snow and ice are light-coloured and shiny, resulting in more solar radiation reflected and less longwave radiation being emitted in response. → In contrast, if an area warms up, the surface cover of snow and ice might shrink, decreasing the area's albedo as bare earth is revealed and grassland colonies in the area. This results in more solar radiation absorbed and longwave radiation emitted. → Desertification and deforestation lead to increased albedos as sand has a higher albedo than soil and vegetation. E.g. during the 20th century, albedo in the Sahel, Africa increased from 14% to 35%.
France Heatwave in 2003
→ A particularly severe heatwave in the summer of 2003 resulted in more than 70000 excess deaths across Western Europe. → 15000 people were killed in Paris as a result of the heatwaves → Infrastructure and health system could not handle the scale of the deaths. → Over 3000 people died in one night.
Greenhouse Effect
→ A phenomenon in which the atmosphere of a planet traps radiation emitted by its sun, caused by gases such as carbon dioxide, water vapour, and methane that allow incoming sunlight to pass through but retain heat radiated back from the planet's surface. → The greenhouse effect is a result of environmental and natural causes.
Kyoto Protocol 1997
→ Aimed to cut emissions of greenhouse gases across the developed world by about 5% compared with 1990. → Developed countries are responsible for the high levels of GHG emissions due to industrial activity, the Protocol places a burden on developed nations under the principle of "common but differentiated responsibilities." → Parties were made to prepare policies and enact measures to reduce GHG emissions, increase absorption of GHGs, and utilise technology and mechanisms to create a system that will give "credits" to earn to be able to emit GHGs on a local scale. → Many countries were allowed to increase pollution, including all those in the developing world. → A total of 192 countries have signed and ratified the Kyoto Protocol, including, Japan, Australia, Canada, Botswana, etc. The only nations that have not signed the global climate treaty are Afghanistan, Sudan and the U.S.A. → Due to many prominent carbon-emitting nations (China, other MICs) not being in the agreement, success is limited. → According to the Guardian, Europe's savings reduced to 1% from 1990 to 2008 and the developed world as a whole seeing its emissions increased by 7% in the same period. The original average target of cut was around 5% from 1990 - 2012. The original 5% cut was insignificant in the first place → However, monitoring and verification systems, carbon markets, technology transfer and funds for adaptation have all been mobilised by Kyoto.
Case Study: Bangladesh Climate Change and Migration
→ Bangladesh's Prime Minister Sheikh Hasina told the UN that a one-metre rise in sea level, would submerge a fifth of the country and turn 30 million people into "climate migrant. → Bangladesh may lose 15-20% of current land mass due to increasing sea level. → Sea level rises, sends salt water into the Kolbari village, flooding the paddy fields and killing trees. → A 2014 slum census found the number of people living on the margins of cities had doubled to 2.2 million since 1997. Meanwhile, the population in southwestern coastal regions is declining. → 20 million Bangladeshis are said to be living illegally in neighbouring India. → Bangladesh's government helped build a three storey cyclone shelter in Kolbari village. → Land used by farmers to harvest rice crop is too salty. → Farmers are adapting to fattening shrimp and crab which can tolerate higher salinity. → Bangladeshi population are unable to consume shrimp and crab as it is forbidden for the Muslim majority. → A small plant has been developed in Kolabri village to export shellfish to China and Malaysia, in which there is a higher demand for these products.
Soil
→ Basis of all life on Earth → Formed from the decomposed rock (weather and animals) → Takes 2000 years to form 10 cm of soil 13 million hectares of forest are cut down annually exposing soil (exposed to wind and water) → Unsustainable farming practices (e.g slopes) remove trees (fold soil together), monocultures (remove nutrients). When harvesting soil is exposed (accelerates erosion). → 24 billion tons of fertile soil were lost in 2011 (3.4 tons per person). → Cities cover soil and take fertile soil away from potential agriculture. → Available arable (farmable) land or inhabitant will be reduced by half by 2050. → Sustaining soil can be executed through governmental policies, regulate urban development (vertical rather than sprawl).
Loess Plateau, China : Soil Rehabilitation Project
→ Became one of the most degraded places on Earth due to thousands of years of unsustainable farming practices. → The World Bank and the Chinese government partnered to devise a rehabilitation scheme in 1994. → Strategies involved getting local farmers on board too: Plant trees (270,000 hectares) Build small dams Terrace some slopes (72,000 hectares) Keep goats in enclosures Dune stabilisation by planting → Within 10 years the ecosystem was restored. The land became productive again. The hydrological system was restored, reduced flood risk and it quadrupled the farmer's incomes.
Biosphere
→ Biosphere comprises all the living organisms on the Earth. → Includes living organisms located in the lithosphere (under the surface of the Earth), atmosphere, or hydrosphere.
Bird Migration
→ Birds migrate less far South during winter due to rising temperatures → Earlier onset of spring - 28 species now nest earlier in the year in North America → Many birds begin migrating north 13 days earlier than they used to 100 years ago → 16 species of butterfly begin their annual migration earlier than in the past. → Many species of bird no longer migrate as far south as they used to winter, e.g. snow goose. This is called 'short stopping'. → Some species are migrating upwards, e.g. up to the Andes.
Biosphere Carbon
→ Burning of deforested trees releases the stored carbon. → Some countries have afforestation programs and Asia has actually had an increase in forest cover (more sequestration). → Reducing unsustainable consumption is the only way to work and protecting indigenous rights to the forest area. → UN, World Bank are devising policies to combat change. ↠ REDD is a program which gets money for forest protection by measuring/quantify emissions reduction from not cutting down trees, then paying people to leave the trees in place. ↠ Selling carbon credits for rich countries and companies to offset their removal of forest or carbon emissions.
Give an example of three of these movements in the cycle
→ Carbon in the atmosphere is used in photosynthesis to create new plant material. This process transfers large amounts of carbon from one carbon pool (the atmosphere) to another (plantation). The plant material releases carbon dioxide back into the atmosphere through respiration. → Carbon from dead plants can be embedded into the soil, in which it may reside before being degraded by soil microbes and released back into the atmosphere. The plant material will decay and is harvested by humans or burned for energy or in wildfires. These processes are fluxes that transfer carbon between several carbon pools (releasing back into the atmosphere). → Organic materials that have been buried in deep sediments (and protected from decay) was slowly transformed into deposits of coal, oil and natural gas, the fossil fuels that are burned to create electricity, however, contribute to an increase in carbon dioxide emissions into the atmosphere.
Negatives of Agricultural Output
→ Changing climate contributes to several resource problems such as food security, water scarcity, pollution and soil degradation. → Productivity levels are expected to be lower with climate change, due to temperature changes, crop water requirements and water availability and quality. → 17% of greenhouse gases are the result of agriculture plus 7 to 14% through land use changes (deforestation to create farmland, forms etc). → The main direct agricultural GHGs are nitrous oxide from soils, fertilisers, dejections from grazing animals, and methane production and paddy rice cultivation. → Accounting for 58% of total anthropogenic nitrous oxide emissions and 47% of total anthropogenic methane emissions, → In OECD countries, the agriculture sector accounts for 8% of total average GHG emissions, but the sector's contribution varies significantly across countries
Climate Change Effects on Health
→ Climate change affects the social and environmental determinants of health - clean air, safe drinking water, sufficient food, and secure shelter. → Between 2030 and 2050, climate change is expected to cause approximately 250 000 additional deaths per year, from malnutrition, malaria, diarrhoea and heat stress. → The direct damage costs to health (i.e.excluding costs in health-determining sectors such as agriculture and water and sanitation), is estimated to be between USD 2-4 billion per year by 2030. → Areas with weak health infrastructure - mostly in developing countries - will be the least able to manage without assistance to prepare and respond. → Natural disaster (extreme weather) will cause more injury related deaths.
Food Production
→ Currently, a small number of countries are responsible for growing the majority of the world's wheat crop that is sold on the world's markets. The 'wheat belts' in countries such as the USA, Canada and the Russian Federation are in the interior of the countries. Wheat companies such as Cargill, General Mills, ADM. → Climate change could affect these yields (and future prospects) in a detrimental way, e.g. through droughts, changes in temperature, precipitation, or flooding, etc. → This will affect the economies of the 'wheat belt' countries but also the world's food supply.
Species
→ Each species within an ecosystem fills an ecological niche → Ecological niche is a particular function within an ecosystem → When an ecosystem is disturbed, it can level and ecological niche vacant → Removal of species ⟶ Reduces the flow energy in the ecosystem ⟶ Causes stress and possible breakdown of the ecosystem
Ecosystems
→ Ecosystems are vulnerable to climate change because they function within narrow tolerance levels. → Tolerance levels is the range of conditions that an organism can withstand. → This means that if there is a slight change in temperature, water levels or purity or vegetation cover the ecosystem could collapse. → All ecosystems have a limiting factor that controls their stability and vulnerability to climate change, e.g. a desert's limiting factor is water, a glacial area's limiting factor would be a lack of incoming solar radiation. → Ecosystems have three critical limiting levels of limiting factors: ↠ Minimum level where productivity decreases ↠ Optimum level where productivity is greatest ↠ Maximum level where productivity decreases.
Extreme Weather
→ Extreme weather includes unexpected, unusual, unpredictable, severe or unseasonal weather; weather at the extremes of the historical distribution (the range that has been observed in the past). → The impact of climate change is more than just a simple increase in temperature. → The extent of global warming varies in different parts of the world, with temperatures rising more in the polar regions than the equatorial and tropical regions. → Temperatures are also increasing more in inland areas than coastal areas. → Climates are becoming more variable, deviating from long-term averages, leading to extremes of heat and cold, wet and dry.
Feedback Loop
→ Feedback loops occur when the output of a system circulate back and become inputs in a succession of cause-and-effect cycles. → Natural/human sources of methane ↠ Adds to greenhouse gases ↠ Traps more longwave radiation within atmosphere ↠ Increasing global temperature
Global Dimming
→ Global dimming is a decrease of insolation reaching the Earth's surface. → The most common cause of global dimming is minute particles that are suspended into the Earth's atmosphere which absorb and reflect radiation back into space. → The two most common natural sources of airborne particles are fires and volcanic eruptions. → Global dimming has two main impacts on climate, causing a cooling of the Earth's surface and a reduction of evaporation that leads in turn to a reduction of precipitation.
What is the correlation between carbon dioxide emissions and economic development?
→ HICs emitted the most CO2/capita during the period of 1970-2012 (around 16,000 tonnes/capita). → Low greenhouse gas/capita tend to be poorer countries with low levels of industrialisation located in regions such as South Asia, Sub-Saharan Africa, and North-western South America. → The USA and Russia have high emissions due to old relatively inefficient technology in the industry. → Middle Eastern countries have high emissions as oil is so cheap that there is no incentive to conserve use. → There is a positive correlation between economic development and CO2 emissions. As countries usually become developed through industrialising and this is where most emissions come from i.e. factories.
Thermosphere
→ Highest layer of the atmosphere → 80+ kilometres above sea level → Gases, which include oxygen, hydrogen and nitrogen, are very thin and similar to a vacuum. → Gases absorb UV radiation from the Sun and therefore heat up to high temperatures of 200C to 1000C.
Shortwave Radiation
→ Hot bodies give off shortwave radiation (ultraviolet light). → Sunlight is electromagnetic radiation given off by the Sun. → On Earth, sunlight is filtered through the atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon.
Hydrosphere
→ Hydrosphere is the combined mass of water found on, under and above the surface of the planet. → Includes all forms of water (solid, liquid, gas and whether fresh or saline).
What would happen to longwave radiation if the shortwave radiation increased?
→ If one of the components of the Earth's energy balance changes the amount of longwave radiation emitted by the Earth into space, the temperature of the Earth will also change. This will result in a new radiative equilibrium. → If the amount of shortwave radiation increased the amount of longwave radiation would also increase. The temperature of the Earth will increase, resulting in a new radiative equilibrium.
Why does land ice contribute more to sea level rise than sea ice?
→ In terms of sea levels, melting sea ice will not have a significant impact. This is because the floating ice already displaces roughly the same amount of water as it would produce when it melts, therefore the effect would be negligible. Furthermore, most of the Earth's ice, more than 95% is land based and contained mostly in enormous ice sheets across Greenland and Antarctica (in which there are entire mountain ranges completely encapsulated by ice). → However, if land ice melts, the oceans will have more water, therefore the sea levels as measured from coast will increase roughly by 70m. Half of the globes population resides in coastal areas (for commerce and trade). A rise of 10m (in sea level) will displace 630 million people (nearly 10% of the globes population), at 25m rise, 1.4 billion people, roughly 20% of the globes population will be homeless.
Enhanced Greenhouse Effect
→ It is referred to as climate change or global warming. → It is the impact on the climate from the additional heat retained due to the increased amounts of carbon dioxide and other greenhouse gases that humans have released into the Earth's atmosphere since the industrial revolution. → The enhanced greenhouse effect is a result of human activity.
Air Circulation
→ Large-scale air circulations are set up through this process. The ones above the equator are called Hadley cells. → Further north and south are other circulations called Ferrel cells and finally polar cells. → The job of each of these is to redistribute energy. In doing so, they create our weather and climate.
Disparities in Exposure to Climate Change
→ Levels of climate change risk and vulnerability will vary according to a person's location, wealth, social differences (age, gender, education) and risk perception. → Vulnerability global climate change refer to the degree to which people are susceptible to, or unable to cope with, the adverse impacts of climate change. The main factors associated with vulnerability: → Exposure → Sensitivity → Adaptive Capacity: The degree to which they could mitigate the potential harm by taking action to reduce their exposure or sensitivity. → Some population groups are more vulnerable to climate change than others. These include the youth, elderly, population with disabilities, minority groups, refugees and indigenous people. Women generally are more vulnerable because of their burden to care for the youth, the elderly and the sick. Sick-parent households are often very vulnerable to climate change. → Some locations are more at risk than others, including, low lying islands, river mouths and valleys, coastal areas and regions that derive their water supplies from mountain glaciers. Islands in the Indian Ocean and the Pacific Ocean are among the areas that are most vulnerable, including Kiribati, Tuvalu, and the Marshall Islands, the Maldives, and Antigua and Nevis in the Caribbean.
Effects of Latitudes
→ Low latitudes (near the equator) receive more intense solar radiation. The rays hit directly and have less atmosphere to pass through. → At high latitudes (near the poles), the rays hit at a low angle and therefore the same amount of heat is spread across a large area. There is more atmosphere to pass through and therefore there is more absorption and greater scattering of the energy. → Due to uneven heating, large convection cells (Hadley cells) are created north and south of the equator. These cells are able to redistribute the heat energy to higher latitudes. As air descends and heats up the Earth's surface it releases longwave radiation.
Troposphere
→ Lowest layer of the atmosphere, in which weather occurs. → Contains most mass of the atmosphere, including most of the water, dust, vapour and pollution. → Heat is reflected from the Earth's surface and clouds. → Temperature declines by 6.5C every 1000 meters rise in altitude.
Patterns on Vulnerability
→ Many of the people at risk are located in southeast Asia, particularly in countries such as India and Bangladesh. → North America, South America and Australia are relatively low in terms of people at risk. → Sea level rise is a potential risk for countries all around the globe. It is particularly high for countries in Asia, such as Japan, Vietnam and the Philippines. → Areas that are at low risk to sea level rise include landlocked regions such as Niger and the Middle East. → Fastest growing populations have historically contributed to increasing carbon dioxide emissions due to urbanisation and technological advancements. → Poverty is generally concentrated in countries in southeast Asia such as India and Bangladesh, as well as countries in Africa.
What is sea ice's contribution to sea levels?
→ Meltwater from sea ice and floating ice shelves may add 2.6% more water to the ocean than water displaced by ice, or the equivalent of approximately 4 meters. → Noerdlinger notes that because freshwater is not as dense as saltwater, freshwater has a greater volume than an equivalent weight of saltwater. Hence, when freshwater ice melts in the ocean, it contributes to a greater volume of melt water than it originally displaced.
Human Sources of Methane
→ Methane is another significant greenhouse gas. It is a major component of natural gas, and as such, it occurs naturally and abundantly underground and beneath the ocean floor. → Methane is created in the upper level of the Earth's surface of microorganisms in the process of methanogenesis, and then released into the atmosphere. → Methane has 86 times greater Global Warming Potential (GWP) than carbon dioxide over a period of 20 years. → Methane GWP is 34 times greater GWP than carbon dioxide over a period of 100 years, as a lower figure than the 20 year number because of methane relatively short atmospheric lifetime.
Ocean Currents
→ Oceanic convey belt (the ocean currents) → Oceanic circulations also help to transfer heat energy by moving warm and cold water around. Thus energy is balanced by these two processes. → Water chimneys are found near the poles. This is where water flows downwards like a riptide. This is due to diluted saltwater from ice caps and from convection currents. → With global warming the water chimney near the northern pole may stop. This will cause the water to cool so much that a mini ice age might happen again.
Ocean Carbon
→ Oceans have absorbed approximately 50% of the extra heat released by human activity. → Ocean is 30% more acidic as a result of the carbon dioxide emissions. Warm water absorbs less carbon dioxide than cooler water → As the carbon dioxide (that is absorbed) in the water increases, it changes the concentration (of the water) and causes it to become more acidic. In addition, results in the formation of carbonate. This environment means it is more challenging for some marine species to develop hard protective shells and as result become more vulnerable to predators. This can lead to food shortages as 1 in 7 relies on seafood as their main protein source. → Corals are not able to survive as the acidity levels are too high. These are biodiversity hotspots with 25% of all sea species. → Shallow waters are impacted much more than deeper waters. Shallow waters is where most sea life is located.
Plant Migration
→ Plants migrate towards the north → This primarily happens through seed dispersal → Climate change could benefit some areas with increased vegetation coverage, whereas other areas will lose vegetation coverage. → This would be because of differing levels of carbon dioxide and rainfall in different areas → It is estimated that both plants and animals are moving to higher elevations at a rate of 11m per decade, and to higher latitudes at a rate of 16.9km per decade. → Some species are experiencing an expansion of habitat, others a significant reduction in habitat area. → Any change to a plant or animal species within an ecosystem will have impacts on other plants and animals species.
How can human activity cause fluxes to occur focussing on fossil fuel combustion and land use change?
→ Scientists have shown that the increase of carbon concentration in the atmosphere is a result of human activities that have occurred over the last 150 years, including the burning of fossil fuels and deforestation. Because CO2 is a greenhouse gas, this increase is believed to be causing a rise in global temperatures. This is the primary cause of climate change and is the main reason for increasing interest in the carbon cycle. → The most important cause is the combustion of coal, oil and natural gas. Fuels have been mined and combusted at increasing rates and have served as a primary source of the energy that drives modern industrial human civilization. At present, fossil fuel combustion represents a flux to the atmosphere of approximately 6-8 PgC/year.
Animal Migration
→ Subspecies of polar bears are moving north to where there is more persistent year-round sea ice. → There's been a 40% decrease in polar bear numbers in part of the Arctic since 2001.
Impact on Food Production
→ The global pattern of crop yield is expected to be affected by climate change. The world's most important food are rice and wheat and these are grown in distinct regions. → Almost every country depends on food imports and at any given moment the world has about 40 days worth of food supply in store. → If climate change reduces harvests significantly then food prices will rise and some populations will be very badly affected, especially in Sub Saharan Africa.
Soil Degradation
→ The loss of quality and/or quality of soil → Soil quality is how fertile soil is, therefore by losing nutrients soil is degraded. This can be through leaching, in which water dissolves minerals out of soil. → Soil quantity is lost through erosion. This can happen through being washed away, e.g. rain, or blown away by wind. → When the soil is damaged it releases carbon dioxide. → Many of the globes cultivated soil has lost more than 50% of its carbon. → 4 per 100 carbon sequestrations (removal) in soils for food security and the climate. → The quantity of carbon contained in the atmosphere increases by 4.3 billion tons every year. → The world's soil contains 1500 billion tons of carbon in the form of organic material. → If we increase by 0.4% a year the quantity of carbon contained in soils, we can halt the annual increase in carbon dioxide emissions in the atmosphere
Global Patterns of Agricultural Productivity
→ There are more countries that will have a loss or detrimental percentage change in agricultural productivity (less agricultural productivity). → Many regions in the tropic of cancer have high percentage change in agricultural productivity (more agricultural productivity). → Generally, most of the countries in Africa aside from Egypt and Kenya will have a loss of agricultural productivity from 0 to -50%. → Canada and Scandinavia will have an increase in agricultural productivity from +15% to +35%.
Sun
→ There is a Sun cycle which is around 11 years. This is significant because more solar radiation is emitted from the Sun during the time around the solar maximum when sunspot activity is greatest. → Sunspots are dark areas on the Sun's outer layer (photosphere). They are regions of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection. → The point in the cycle in which the Sun's magnetic field is strongest correlates to the point of maximum sunspot activity and is known as the solar maximum.
Glacial Carbon
→ There is organic carbon in glaciers. → It's in a form that is easily changed and absorbed. → It's very attractive for microbes to digest. → This impacts the food chain in aquatic and marine environments, i.e. microbes multiple ⟶ plankton eat the microbes and multiply ⟶ fish eat plankton etc.
Carbon Emission Offsetting
Changing behaviours and/or machinery, vehicles, energy sources to reduce carbon emissions, i.e. stopping emissions that would happened otherwise (mitigation strategies).
Product Risks
Companies core products become unpopular and perhaps impossible to sell. EXAMPLE: Air conditioning factories that lose market share to alternative cooling technologies, and ski resorts that lose business because they can no longer rely of sufficient snow cover.
Heat Waves Effects on Economics
Global labour capacity of rural labourers, such as farmers, has fallen by 5.3% from 2000 to 2016 due to rising temperatures and the inability to work as the climate is too hot.
Reputation Risk
Occurs when the public perceives a corporation's activities as harmful for the environment. EXAMPLE: Loss of sales or business, consumer boycotts, and community protests.
How much radiation does the Sun absorb?
The Earth absorbs about 70 percent of the solar energy radiation reaching it and therefore reflects the other 30 percent.
Longwave Radiation
→ Cold bodies give off longwave radiation (infrared light). → The Earth emits low energy infrared radiation.
Positives of Agricultural Output
→ Technical practices that mitigate GHG emissions underscore the potential of the agriculture sector to be part of the fight against climate change. → From 1990 to 2010, agricultural production volume increased by 1.6% per annum, resulting in annual reductions of 2.0% in the emissions intensity of agricultural output. → Productivity growth has been maintained in the because farmers have been independently taking measures to adapt to climate change. → Accounting for the additional production risks created by climate variability as well as the need to achieve higher productivity to improve resource-use efficiency.
Case Study: Solar Power in the Sahara
By capturing 0.3 percent of the solar energy that reaches the Sahara could supply all of Europe's energy needs. 100 kilometer squared of solar panels are being installed by Noor Energy. Noor Energy to supply Europe via undersea cables (in southwest Tunisia).
How does the carbon cycle link into the atmospheric energy budget?
Carbon dioxide (CO2) is important because it contributes to the greenhouse effect, in which heat generated from sunlight at the Earth's surface is trapped by certain gasses and prevented from escaping through the atmosphere.
Where is Carbon present?
Carbon is present in the Earth's atmosphere, soils, oceans, and crust.
Trend of Average Global Temperatures Between 1880 to 2010
Overall, there is an increase in the average global temperature between 1880 to 2010. There is a minor increase between 1880 to 1940, then a constant measure between 1940 to 1980, and a dramatic increased from 1980 to 2010.
What is radiative equilibrium?
→ Radiative equilibrium is the energy balance between the amount of solar radiation absorbed by the Earth and the amount of longwave radiation emitted by the Earth into space. → It allows for the Earth's temperature to be relatively constant. → It tells us that the amount of solar radiation absorbed by the Earth will equal the amount of longwave radiation emitted by the Earth into space.
Case Study: Nicaragua
→ Refused to sign the Paris Agreement → Only emit 0.03% to greenhouse gas emissions so don't feel they should be made to comply with a global agreement as it not equitable. → 50% of energy is renewable including geothermal and wind → Highly vulnerable to impacts of climate change
Main Causes of Climate Change
→ Temperature Change → Sea levels → Precipitation
Regulation Risk
Arise when governments impose new requirements on companies because of climate change. EXAMPLE: Regulations may require companies to pay more money to comply with pollution controls or limit certain activities or production processes. Subsidies may be provided for competitors.
Carbon Trading
Companies, individuals and governments who prevent one tonne of carbon emissions can apply for a carbon credit (each carbon credit is equal to one tonne of carbon not emitted). These credits can then be traded, businesses etc, that are big emitters can buy the credits off those who offset the carbon. Therefore, there is economic value in not emitting.
Clean Development Mechanism
Is a carbon emissions trading scheme where developed countries who are bigger carbon emitters can invest in clean energy development projects in poorer countries to offset some of their emissions. Examples include Hydroelectric power plants in Malaysia, Brazil Wind power plants in the Western Sahara Criticisms of these projects include These projects are often on indigenous land and inadequate consultation and/or compensation is offered. They can be hugely disruptive to the way of life.
Mitigation
It is the action taken to reduce activities that are the man-made causes of climate change.
What does the abbreviation 'pg' refer to and how it is calculated?
Petagrams also know as Gigatonnes of Carbon.
What is the relationship between carbon sources and carbon sinks?
Sources add carbon to the atmosphere, whereas sinks remove carbon from the atmosphere. If all sources are equal to all sinks, the carbon cycle can be said to be in equilibrium (or in balance) and there is no change in the size of the pools over time. Maintaining a steady amount of CO2 in the atmosphere helps maintain stable average temperatures at the global scale.
Air Pollution Effects on Health
→ Poor air quality impacts health by increasing the rate of stroke, heart disease, lung cancer and chronic and acute respiratory diseases. → Air pollution from a range of sources contributed to over 1.9 million premature deaths across southeast Asia in 2015.
Vulnerability in the USA
→ Poorer people are more at risk → Population is unable to afford insurance → May not be documented (no protection) → Low-lying areas are more vulnerable (Florida, Louisiana)
