Global Climate Change and environmental problems Flashcards
2 (25 cards)
What is climate?
Climate refers to time and space patterns of precipitation, temperature, and wind
What is climate change?
Climate change occurs when the patterns change in time and space
What are the timescales over which climate changes naturally?
- Decadal (10’s of years)
- Centennial (100’s of years)
- Millennial (1000’s of years)
- Longer (glacial cycles, e.g. Ice Ages)
What are the spatial scales of natural climate change?
- Local
- Regional
- Global
Define Greenhouse Gas.
Gas that absorbs infrared radiation
Give examples of Greenhouse Gases.
- Carbon dioxide
- Methane
- Nitrous oxide
- Chlorofluorocarbons
- Tropospheric ozone
What is positive feedback in the context of climate change?
Change in some condition triggers a response that intensifies the changed condition
What is infrared radiation?
Radiation that has a wavelength longer than visible light, but shorter than radio waves
What is the Greenhouse Effect?
Increase of heat in a system where energy enters as light, is absorbed as heat, and released later
List human activities that affect greenhouse gas levels.
- Agriculture
- Deforestation
- Fossil fuel use
- Cement production
What is the most abundant greenhouse gas?
Water vapor
How do higher temperatures affect water vapor?
Higher temperatures increase evaporation and water vapor, trapping more heat
How much more effective is methane than CO2 in heating?
20 times more effective
What are the main sources of methane emissions?
- Livestock
- Landfills
- Coal mines
- Natural gas
- Rice cultivation
- Manure
What is nitrous oxide and its increase over the last 200 years?
Nitrous oxide has increased 18% and comes from various sources including agriculture and fossil fuels
What are the sources of ozone as a greenhouse gas?
- Traffic
- Forest fires
- Agricultural wastes
What are CFCs and their impact?
CFCs are anthropogenic, long-lived greenhouse gases causing warming and ozone destruction
What is radiative forcing?
Contribution of each greenhouse gas to climate change
What percentage of increased CO2 stays in the atmosphere?
About 50%
What causes the upward trend of CO2 in the atmosphere?
Carbon released from fossil fuels and soils, as seasonal cycles cannot explain it
What are the sources of carbon dioxide emissions?
- Burning forests
- Deforestation
- Human activities
What are the sinks for carbon dioxide?
- Oceans
- Forests
What major conclusion did the IPCC’s Fourth Assessment Report (AR4) reach?
Warming of the climate is unequivocal
What is the major greenhouse gas identified in the IPCC report?
CO2
