Geography - Case Studies Flashcards
Impact of global dimming on climate change
The volcanic eruption of Mount Pinatubo, Philippines in 1991 led to a drop in average global temperature of about 0.6 Degrees Celsius over 15 months after the eruption.
Impact of the burning of fossil fuels on global warming
Emerging Economies; areas that are most populated like China and India (Asia) produce large amounts of carbon dioxide and other greenhouse gases. Globally, the burning of fossil fuels produces 40 billion tonnes of carbon dioxide annually.
Impact of rising sea levels on humans
In Tuvalu, rapidly rising sea levels are threatening to swallow the island. Every time the tide rises by 1 and a half metres, the island floods. Almost the entire country will be underwater within 50 years.
In the Sundarbans, floods are taking away people’s homes and farmland, ridding them of their main source of income. Farmers are not equipped for other jobs → livelihood affected. Young men have to migrate to the cities for work.
Impact of droughts on humans (the Sahel)
Sahel, located in Africa, provides Africa with food and cash crops such as millet and cotton. Increased ocean temperature → smaller temperature gap between land and ocean → monsoon rains reduced → less rainfall → leads to droughts. Leads to crops failing and livestock dying, potentially bringing famine and hunger. Lost income causes unemployment. Food prices increase as there is less food. Clean water is unavailable, increased use of contaminated water and spread of diseases. Women and children travel farther to get water → children miss school + they get back problems from carrying heavy loads.
Impact of coral bleaching and ocean acidification on the environment
The Great Barrier Reef, located in Australia, was severely affected in 2016 and 2017 due to rising sea temp, worst bleaching on record. Up to two-thirds of corals died in the northern section (29%). Species diversity decreased. Average coral cover dropped 30% from 1960s partly due to ocean acidification.
Impact of disruption of marine food webs + composition changes on the environment
Tropical species such as parrotfish and rabbitfish have migrated polewards. Diversity of species in tropical waters has dropped significantly in the last 50 years. Parrotfish and rabbitfish feed on kelp → pop. decrease of kelp → affects other species depending on it for food and protection from predators. In Japan, pop. of lobsters and abalone dropped due to the disappearance of kelp.
Species (e.g. corals) unable to migrate may die if unable to adapt; face local/global extinction.
Impact of changes to geographic distribution in terrestrial species on animals
Wallabies in Australia are migrating to higher altitudes. Herbfields become a source of food and they have flourished. However, overgrazing threatens to reduce them to grassy lawns. Other species depending on herbfields such as the broad-toothed rats face greater competition, higher risk of extinction.
Impact of changes to geographic distribution in terrestrial species on forests
Temperate forests are advancing northward and replacing boreal forests. Boreal forests are advancing northward into the tundra.
Impact of droughts on flora and fauna
Droughts in California between 2012 to 2016 contributed to the death of 102 million forest trees due to lack of water and spread of diseases. Dried up wetlands caused deaths of insects, fish and plants → migratory birds die of starvation. Thousands of ducks crowd in remaining wetlands and spread cholera → many died.
Impact of excessive rainfall on flora and fauna
Parts of Hereford, England were continuously flooded since October 2020. Affected burrowing animals due to limited access to dry land, disrupted hibernation cycle. Dangerous for the animals. Suffocated, drowned and weakened plants and other insects (disrupted food web). Waters polluted with sediments, run-off and pollutants. Animals have no source of clean water. Water visibility decreased, animals cannot hunt.
Impact of heatwaves on humans
2003 European heatwave where around 70,000 people died, lasted for 2 weeks. Harvest for wheat was affected as many crops died. Increased price for bread and food was less affordable.
Impact of wildfires on humans
(Australia) 2019-2020 widespread wildfires that affected the entire continent. Difficult to get under control due to dry conditions. Hazardous air quality, human health risk. In Sydney, air quality was 11 times greater than what is set at a hazardous level. 24 people died, thousands of buildings burnt down. Many left homeless.
Impact of floods on humans
Bangladesh is densely-populated and low-lying with many people living near coastal areas, and often experiences seasonal flooding due to monsoon climate. Vulnerable to coastal flooding by rising sea levels. Worst monsoon in 2020 due to intense rainfall; deaths of 260 people, 1.3 million homes destroyed; million dollars’ worth of agricultural crops lost, which is substantial for Bangladesh as it is a developing country.
Impact of tropical cyclones on humans
Six tropical cyclones over 4 weeks in the Phillipines, 2020. Strong typhoon, Typhoon Goni, brought about destructive winds and high rainfall → loss of lives, massive property destruction, nearly 1 million people evacuated, $36 million worth of crops damaged, power supplies cut. Philippines’ infrastructure was not able to cope with severe flooding. Communities had no time to recover in between cyclone hits.
Impact of fish production on humans
In the Tonle Sap Lake in Cambodia, fishing is a main economic activity. Climate change led to: increased temp, unpredictable rainfall, water levels in Lake decreased, reduced availability of fishes. Higher temp means forests burn more easily during dry season; destroys fish habitats, reduced fish availability.
Conversely, fishermen in Portugal have begun to catch new species which were previously found in warmer regions.
Impact of increase in vector-borne diseases on humans
Mosquitoes were nonexistent in the Bhutan mountains before 2018 (too cold to breed). In 2019 they suffered the first national dengue epidemic, many parts of country reported the virus.
Impact of the melting of permafrost on humans
In 2016, a summer heat wave in western Siberia increased atmospheric temperatures and led to the melting of permafrost (permanently frozen ground). This permafrost contained the disease known as ‘anthrax’, which had killed thousands of reindeer and affected dozens of humans in the 1800s.
Impact of droughts on political stability
In Northern Cameroon, 2019, violence erupted between herders and fishermen over dwindling water resources linked to climate change. Hundreds were killed, and tens of thousands fled to Chad to escape the conflict. Lake Chad’s shrinking water supply (due to climate-induced drought) worsened tensions between farmers, fishermen, and herders.
