Exam 10: Climate-Past, present, and Future

El NinoSouthern Oscillation phenomena seem to be cyclic,recurring every four to seven years.

Increased levels of carbon dioxide in earth's atmosphere will definitely result in increased crop yields.

When water evaporates from the oceans,

Water vapor is the most significant greenhouse gas in terms of average atmospheric concentration (2 to 3%),but its amount varies quickly over a matter of days,whereas the average level of carbon dioxide changes much more slowly.

Global warming is not uniform throughout the earth as some places it is more severe than others.

The limited resolution of global climate models makes it difficult to project small-scale,local climatic variations.

Concerns about greenhouse-effect heating relate not only to possible changes in temperature,but also to possible changes in precipitation patterns.

Studies of cores from polar ice sheets indicate a correlation between greenhouse-gas concentrations and temperatures but do not indicate cause-and-effect.

Indicators of past global air or water temperatures include all of the following except

Climate changes can influence the spread of number of diseases such as mosquito borne dengue and malaria,as well as the ones spread by waterborne bacteria and parasites.

A combination of winds that push the ocean currents and differences in oceans' water density that is driven by oceanic circulation,which is related to

The melting of sea ice

All of the following could cause global cooling except

It is difficult to determine the effect of CO₂ on climate because the atmospheric concentration of methane,another "greenhouse gas" is so much greater.

Global warming may increase the number of heat related deaths during summer.

Many Pacific Island nations consist of a collection of atolls.Some of these nations have appealed to the United Nations claiming that rising sea level is causing coastal flooding.Another explanation for coastal flooding on these islands other than rising sea level is

If all the polar ice sheets were to melt,world sea levels would rise only 1 to 2 meters.

Seattle,Washington is located at 47.5 ^$\circ$ N latitude and Boston,Massachusetts is located at 42.22 ^$\circ$ N latitude,so Seattle is farther north than Boston.Both cities border oceans,the Pacific Ocean in the case of Seattle and the Atlantic Ocean in the case of Boston.Both cities are in close proximity to a segment of the global thermohaline circulation system,the Japanese Current for Seattle and the Gulf Stream for Boston.Seattle,though,rarely experiences winter snowfall,whereas Boston often does.Why?

The changes in permafrost has very little effect on traditional lifestyles of local population,animal migrations,and ecosystems.

The principal source of rising levels of carbon dioxide in the atmosphere is the burning of fossil fuels.