5 Written Questions
4 Matching Questions
- what is the difference between weather and climate?
- can you figure out why O18 increases (relative to O16) in the tests of foraminifera during cold intervals, but decreases (relative to O16) during cold intervals in water samples from ice cores?
- what are some climate proxies?
- how do we know that CO2 is coming primarily from fossils?
- a weather refers to the state of the atmosphere at a given time and place; climate is a description of aggregate weather conditions based on observations over many decades; climate is often defined as "average weather"
- b in ice, O18 increases relative to O16 during warm intervals. IN forarms, O18 decreases relative to O16 during warm intervals. Ice cores go back more than 400,000 years and record oxygen isotopes (T), atmospheric CO2 and methane in trapped air bubbles. The O isotope record form forarms "mirrors" that from glacial ice.
- c ...
- d (1) seafloor sediments- contain remains of organisms that one lived near sea surface; useful recorders of worldwide climate change
(2) oxygen isotope analysis- based on precise measurement of the ratio bt 2 isotopes of oxygen; O^16 is most common and the heavier O^18: O^18/O^16 ratio in shells of microorganisms- past temperatures
(3) climate change recorded in glacial ice
(4) tree rings- archives of environmental history
(5)fossil pollen, corals, historical data
5 Multiple Choice Questions
- the fraction of the total radiation that is reflected by a surface; thus the albedo for Earth as a whole is 30 percent
- 1 degree Celsius rise in average temperature; increase greater at high latitudes- but the 10 warmest years have been during the past 15 years!
- hard to predict specific regional changes because increased levels of CO2 but consequences include:
(1) altering the distribution of the world's water resources
(2) a probable rise in sea level
(3) a greater intensity of tropical cyclones
(4) changes in the extent of Arctic sea ice and permafrost
5 True/False Questions
what isotopes form what part of the foraminifera test composition can be used to tell us about past ice sheet volume changes, and ALSO about past changes in ocean water temperature? → foraminifera is a skeleton made of CaCO3 (same as calcite) oxygen isotope rations depend upon water temp; these tiny, single celled organisms are sensitive to even small fluctuations in temperature; seafloor sedimetns containing fossils such as this are useful recorders of climate change
how far back in time can we trace climate using historical documents? → ...
how do we know what the concentration of atmospheric CO2 was during past glacial and interglacial cycles? where do these samples come from? → 30% higher than highest level over at least the last 650,000 years
stratospheric ozone → forms at ~ 20 - 30 km above Earth's surface, and is a protective layer that helps to filter out UV radiation by absorbing some of its energy. Life on planet Earth needs this because too much UV at Earth's surface (where we all live) can be harmful to cell function.
trophospheric ozone → forms at ~ 20 - 30 km above Earth's surface, and is a protective layer that helps to filter out UV radiation by absorbing some of its energy. Life on planet Earth needs this because too much UV at Earth's surface (where we all live) can be harmful to cell function.