Climate Change Flashcards
What’s going on with Tuvalu?
It’s one of the smallest nations on Earth between Hawaii and Australia. 9 small islands.
Has experienced serious flooding in recent years during storms and high tide
May not be able to support its population in 50-100 years due to rise in sea level
What is climate vs. weather?
Climate is characteristic atmospheric conditions over a long period of time, like years or decades.
Weather is atmospheric conditions over short periods of time.
How are climate zones classified?
Generally by temperature and precipitation, but it might be more complex than that…
Might consider ocean currents, mountain ranges, plateaus.
How does climate influence natural processes?
MAJORLY
- Flooding dependent on rainfall amount and intensity
- Landslides common in areas with rainy climates
- Wildfires more likely in dry areas
Differentiate between permanent gases, variable gases, and aerosols.
1) Permanent Gases: gases whose proportions stay constant, like NITROGEN and OXYGEN. They have little effect atmospherically.
2) Variable Gases: gases whose proportions vary with time and space, like CO2, water vapor, ozone, methane, nitrous oxide, and halocarbons. They have an important role in atmospheric dynamics.
3) Aerosols: particles whose proportions vary with time and space
What is the cryosphere?
The part of the hydrosphere where water stays frozen year-round
Includes permafrost, sea ice, ice caps, glaciers, and ice sheets
Which way to glaciers flow?
From high areas to low areas under the weight of accumulated ice.
Glacial vs. Interglacial Intervals
Glacial: Periods with major continental glaciations; COLD
Interglacial: warmer periods with less glaciations; COLD
Think retreats and advances
What was the Pleistocene Epoch?
The last series of glacial and interglacial periods. Multiple ice ages. When glaciers covered 30% of the Earth.
Today, Glacial ice only covers ~10% of the earth. Nearly all ice is contained in the Antarctic ice sheet
What are the three time periods that we have data from to make climate change predictions?
1) Instrumental Period (measurements of temp made directly since 1860)
2) Historical Record (includes recollections - books, newspapers, journal articles)
3) Paleo-Proxy Record (proxy data can be correlated with climate) (Tree rings, sediments, ice cores)
What is Dendroclimatology?
Climate data provided by tree rings. Extends back more than 10000 years
What are some Paleoclimate Proxy Data sources?
1) Tree Rings; growth of tree rings depends on rainfall and temp variability
2) Sediments; recovered by drilling into ocean or lake and chemicals are interpreted
3) Ice Cores; obtained by drilling into ice
4) Pollen; collects in environments. Types of pollens found reflect climate.
5) Corals; calcium carbonate contains isotopes of oxygen and trace metals that can be analyzed for temperature
6) Carbon-14; can give information about sunspot activity
7) CO2; MOST IMPORTANT proxy for temperature change
What are global climate models? What are the two types?
Mathematical models used to describe natural events. They do not produce data; use data-linked calculations. Two types: General Circulation Models and Global Climate Models.
Differentiate between general circulation models and global climate models.
General Circulation Models: forecast weather.
Global Climate Models: predict climate change.
For global warming, there has been an increase in average temperature of land and ocean during the past _____ years, resulting from burning of ______ _______.
60 years; fossil fuels
What is the greenhouse effect?
The warming of the Earth’s surface and the lower atmosphere.
Some of the infrared radiation passes through the atmosphere but most is re-absorbed and re-emitted in all directions by greenhouse has molecules and clouds.
What does the Earth’s temperature depend on?
a) Amount of sunlight received
b) Amount of sunlight reflected
c) Amount of re-radiated heat that is retained
What are the greenhouse gases?
Water vapour, carbon dioxide (CO2), methane (CH4), and chlorofluorocarbons
_______ ______ accounts for most of the anthropogenic greenhouse effect
Carbon dioxide
Why does climate change? Specifically, what are Milankovich Cycles and Climate Forcing?
Milankovich cycles: natural changes in earth’s orbit, tilt, and precession. Explains SOME changes.
Climate forcing: an imposed change of earth’s energy balance. Positive if increasing, negative if decreasing.
Why does climate change? Specifically, what is the Ocean Conveyor Belt and its relation to the Atlantic Ocean?
Ocean conveyor belt: circulation of ocean water. Can cause fast changes in climate.
In the atlantic ocean, strong northward movement of near-surface waters are cooled when they arrive near greenland. The water cools, become saltier and denser, and sinks to the bottom.
Huge amounts of warm water keep Europe warmer than it would be otherwise.
What are the human-induced components of climate change?
Increased emissions of gases that trap heat
Strong correlation of atmospheric CO2 and global temps
Discuss Solar Forcing
- Relationship between changes in solar energy and climate change
- Medieval Warm Period corresponds to INCREASED solar radiation
- Little Ice Age corresponds to DECREASED solar radiation
- Small effect on climate change, though
Discuss Volcanic Forcing
- Ash from eruptions becomes suspended in the atmosphere, reflects sunlight, has a cooling effect
- Mount Pinatubo (1991) counterbalanced global warming
- Volcanic forcing is bekievde to have contributed to the cooling of the Little Ice Age