Geography year 11 exam Flashcards
Climate Change
Long-term changes in the physical system (biosphere, lithosphere, hydrosphere, atmosphere) that change the Earth’s climate
Global Warming
The gradual increase in temperature in the Earth’s atmosphere
photosynthesis
a process in which they use carbon dioxide (CO2) from the atmosphere, along with sunlight and water, to produce glucose and other organic compounds. This process removes CO2 from the atmosphere and stores carbon in plant biomass..
decomposition
Is the process of breaking down plants. Over vast periods of time, layers of sediment build on each other. Because of the pressure and heat from within the Earth’s crust, it generates fossil fuels
Respiration
During respiration, organic matter is broken down to release energy, and carbon dioxide is produced as a byproduct. This returns carbon to the atmosphere
Combustion
The burning of fossil fuels, including coal, oil, and natural gas, for energy production releases carbon stored in these fuels into the atmosphere as CO2. This is a major source of anthropogenic (human-caused) carbon emissions and contributes to climate change.
Atmosphere (gas)
Layer of gas surrounding the earth
Crucial in regulating climate and weather patterns
Hydrosphere (water)
Refers to all the water on the earth in different formats e.g., oceans, lakes, water vapour, ice sheets
Important to regulate the climate
Lithosphere
The solid outer layer of the Earth.
Responsible for landforms such as mountains, valleys and plateaus
Biosphere (living)
Zone on Earth where life exists
Include all living organisms from plants to animals
Influence by climate, water and geology
Carbon sequestration
The removal/storage of CO2 and other carbon products to reduce the effects of climate change
Greenhouse Gas Effect
Is a natural process that regulates the Earth’s temperature and makes it suitable for life.
Wind Pressure
Wind pressure, or atmospheric circulation, is driven by differences in temperature and pressure across the Earth’s surface.
Warm air rises at the equator, creating a low-pressure zone, and cool air sinks at the poles, forming a high-pressure zone.
Wind flows from high to low-pressure areas, creating global wind patterns, including the trade winds, westerlies, and polar easterlies.
These wind patterns influence weather patterns and climate zones around the world.
Heat Transfer
The unequal heating of the Earth’s surface due to variations in solar energy absorption creates temperature differences between the equator and the poles.
Heat is transported from the equator toward the poles through a combination of atmospheric circulation and ocean currents.
This heat transfer helps maintain temperature gradients and influences the climate zones and seasons experienced in different regions.
Precipitation Patterns
Precipitation patterns are closely tied to atmospheric circulation and temperature.
Warm, moist air rises, cools, and condenses to form clouds and precipitation. This process is responsible for rainfall in many regions.
Rainfall patterns are influenced by factors such as proximity to oceans, mountain ranges, and atmospheric phenomena like monsoons.
This leads to the development of diverse climate zones, including arid deserts, tropical rainforests, and temperate climates.
Convectional Rain
Occurs when warm air rises, cools and condenses = clouds and rain
Tropical/equatorial regions
Associated with hail/grauple
Orographic/Relief Rain
Moist air is being forced to ascend over elevated terrain
As the air rises, it cools and condenses = formation of clouds/rain on the windward (upwind) side of the mountain
The leeward (downwind) side of the mountain receives much less rain (rain shadow)
Cyclonic/Frontal Rain
Two air masses with different temperatures and moisture levels meet
Warm moist meets cold dense
Warm air rises over the colder air = clouds and rain
Widespread and long-lasting
Mid-latitude regions
Ocean Circulation
Ocean circulation is driven by the global wind patterns, temperature gradients, and the Earth’s rotation.
Major ocean currents, such as the Gulf Stream, redistribute heat across the oceans and influence regional climates.
Ocean circulation also affects marine ecosystems, weather patterns, and can contribute to extreme events like hurricanes and cyclones.
Changes in ocean circulation can have significant impacts on climate and weather on a global scale.
Helps trap CO2
Trade Winds
consistent, prevailing winds that blow from east to west in the tropics, roughly between the equator and about 30 degrees latitude in both the Northern and Southern Hemisphere. Depending on the hemisphere, they are called Northeast or Southeast trades
Reliable as they were used for trading
EL Nino
Warm phase- Pacific ocean becomes warm
Atmospheric pressure decreases over the western pacific ocean
Eastern Pacific’s atmospheric pressure rises
Weakening of trade winds- harm to marine ecosystems
La Nina
Cool phase- Pacific ocean
Atmospheric pressure increases over the western pacific ocean
Eastern Pacific’s atmospheric pressure lower
Reinforces normal oceanic patterns and trade winds
IOD
Difference in sea surface temperature between the western Indian Ocean and eastern Indian Ocean south of Indonesia.
Positive IOD
Western part (near Africa) of the Indian ocean becomes warmer, while eastern part (near Australia) becomes cooler
Heavy rains and floods in East Africa, Drought in AUS
Negative IOD
Western part (near Africa) of the Indian ocean becomes cooler, while eastern part (near Australia) becomes warmer
Heavy rains and floods in AUS, Drought in East Africa
High Albedo
100% ray of sun is only reflected at 80% once bounces of light coloured/white surface
Low Albedo
100% ray of sun is only reflected at 10% once bounces of dark coloured/black surface
Anthropogenic biomes
Areas that have experienced sustained human interaction are called anthropogenic biomes
¾ of the Erath’s ground surface has now been directly affected by human activities.
24% of the Earth’s surface is most likely to experience a decline in ecosystem function and productivity
Forests
Dominated by trees
Cover approx. 31% of land surface
Support most terrestrial biodiversity
Contain up to 80% of the total plant biomass
Estimated that 1.6 billion people rely on forests for food, water, timber, clothing, and traditional medicine
Anthropogenic activity is reducing the amount of forest land cover all over the world. This has reduced by 10 million km2. From 50 million to 40 million km2.
Approximately 7.3million hectares are destroyed each year. These are mostly rainforests in Indonesia, Brazil, Thailand and the Democratic Republic of Congo.
A forest’s greatest asset is probably the ability forcarbon sequestration. A healthy growing tree can absorb about 20 kg of CO2each year. A tree that has lived for 40 years will have stored at least a tonne of CO2.
Rainforests
Cover about 6% of the world’s land surface
Found between Tropic of Cancer and Tropic of Capricorn
Believed to produce up to 40% of Earth’s oxygen
Forest clearing (deforestation) is occurring on a large scale in places like Brazil and Indonesia. Trees are cleared and replaced with livestock ranching and farming, plantation agriculture (palm oil and coffee) and mining.
According to the World Wide Fund for Nature (WWF), deforestation is currently occurring at a rate of approximately 27 football fields per minute
Grassland
Grasslands form a transition zone between forest regions and deserts.
Human activities in savanna and grasslands vary from country to country. It is the best biome for agriculture.
Many communities use these areas fornomadic herdingand grazing of livestock, and parts of South Africa, Botswana and Namibia harvest wood, fruit and seeds. In Kenya, Tanzania and Uganda, savanna and grasslands are used as national parks and large-scale safari tourism, which brings money into the country.
Mismanagement of anthropogenic activities in savanna areas, such as over grazing, make them prone to land degradation.
Threats to grassland
Almosthalf of all temperate grasslands and 16 percent of tropical grasslands have been converted to agricultural or industrial usesandonly one percent of the original tallgrass prairieexists today. Specific threats include-
Poor agricultural practicescan ruin soil and strip grasslands of life. If crops are not rotated properly, the soil can become infertile and nothing can be grown for several years.
Monocropping is an agricultural practice thatdepletes the soil’s nutrients.
Toxic pesticidesused in agricultural croplands can bedeadlyfor wild flora and fauna.
Grazing livestockcan consume, trample, and destroy grasses.
Continuedglobal warmingcould turn current marginal grasslands into deserts as rainfall patterns change.
Development of urban areasis increasingly cutting into grassland habitat.
Invasive speciescandisplace native plants and reduce the quality of a grassland. Invasive plants may not be equipped to handle extreme weather, like droughts and wildfires, thus resulting in further habitat loss.
Deserts
Deserts are areas that receive less than 250mm of rain in a year and where land has less than 50 per cent of the ground surface covered by vegetation.
It is estimated that deserts (hot and cold) cover approximately 20 per cent of the terrestrial surface.
Despite their often harsh conditions, deserts are used by people for mining and extensive cattle grazing, scientific observations, remote weapons testing and military bases
Biome Location
Between 15-30 degrees from the equator, due to the high pressure systems at these latitudes.
On the Western sides of continents, due to cold ocean currents (therefore poor evaporation).
High on mountain ranges due to the rain-shadow effect.
Desertification
Desertification is a form of land degradation that transforms land that was once fertile and arable into unproductive arid land.
The continued expansion of desert areas through the process of desertification will have significant ramifications on albedo.
Desert areas have some of the highest rates of albedo and any increase in size will subsequently increase the amount of heat being reflected back into the atmosphere.
Much of the large-scale desertification was originated by poor traditional farming methods that eventually led to erosion and soil loss.
Tundra
Treeless regions found in the Arctic
Extremely cold climate
Very little rainfall
Low biodiversity
Simple vegetation structure
Short season of growth and reproductions (The summer growing season is just 50 to 60 days, when the sun shines up to 24 hours a day.
Energy and nutrients in the form of dead organic material
Large population oscillations
Permafrost- ground that is frozen for 2+ years
Tundra and Climate Change
The oil, gas, and mining industries can disrupt fragile tundra habitats. Drilling wellscan thaw permafrost, while heavy vehicles and pipeline construction can damage soil and prevent vegetation from returning.
Climate change isdriving downpopulations of some Arctic tundra natives such ascaribou (also known as reindeer)
Chemicals used in coolants and aerosol sprays have drivenozone depletionat the North and South Poles, which can let in stronger ultraviolet rays
Permafrost Positive Feedback Loop
Warming creates potentialfeedback loopsthat encourage further destabilization of tundra ecosystems.
As the permafrost melts it releasesmethane, which is a greenhouse gas.
The higher temperatures drive thegrowth of shrubs, which can change soil temperature and prevent snow from reflecting out heat. Which then causes more heating
Causes of Carbon Dioxide
Burning of fossil fuels (coal, oil and natural gas)
50% is being absorbed and other is being released at 0.5% per year
Causes of Methane
Found in natural gas
Burning fossil fuels, ruminant animals, rice paddies and landfills
Methane levels are increasing about 0.9% per year
As permafrost begins to thaw, much of the stores methane is slowly releasing
Causes of Chlorofluorocarbons
Gases used in fridge coolants, A/C, plastic foam (phased out
Causes of Nitrous Oxide
Burning fossil fuels, biomass and some fertiliser
Life span of 150 years are responsible for 3% of global warming
Causes of Water Vapour
Very little effect
Becomes an issue as increased CO2 enables the atmosphere to hold more moisture
Effects of Thermal Expansion
Rising sea levels (20cm by 2030)
Low-lying countries become vulnerable to storm surges and cyclones
Effects of Warmer Oceans
More water vapour in the atmosphere Increases melting of ice
Effects of Glaciers melting
More rapid than usual
Reduces snow cover, reduces albedo
Effects of Changes in Air and Ocean Temperatures
Effects air and water circulation = changes to weather
Extreme weather (hotter and drier) in some places
Indicators
Record high surface air temp
Increased/decreased average number of hot/cold days
Increased intensity and frequency of extreme events
Changing rainfall pattern
Increasing sea surface temp.
Rising sea level
Increased ocean heat content and acidification
Melting ice caps and glaciers
Decreasing arctic sea ice
