help...describe earth's natural causes of global climate change...assignment help!?

Question

Some of the natural causes of the global climate change are - plate tectonics, volcanic activity, and long-term variations in the earth's orbit and the angle of of its rotation axis.

1) Describe each of the natural causes of global climate and explain how can each affect the climate.
2) The climate affects described above occur over long periods of time. Present a scenario by which some natural phenomenon might catastrophically change the global climate on a much shorter time scale.

Thanks!

Answer 1

Q1: There are also irregularitys in the earths orbit that bring it closer to the sun. These irregularitys happen on a 10 - 20 thousand year cycle. The earth also wobbles on its acess, on ithink a 20,000 year ctycle which has effects on global climate.
Also sun spots can play a role these are bursts of increased solar activity which appear as darker spots on the surface of the sun, if during any given period loads of these happen at once the sun can burn a litle hotter, thusly the earth recieves a little more radiation/heat.
Q2: Like the other guys said, volcanoes, meteorites, after a large meteor strikes the planet or after a vast volcanic eruption (some scientists believe there were massive volcanoes called the "decan traps" which caused a massive change in global climate) masses of dust is thrown in to the air which blocks out the light from the sun, this causes many species of plant and animal to dir due to changes in temperature and lack of food.

Answer 2

This is an answer to quesiton two.

When krakatoa blew up there was so much particulate matter blown into the atmosphere that it actually changed to global temperature for a few years afterwards. I think the average temp actually dropped by several degrees due to the nuclear winter type senario.

Also don't foret to include animal and plant causes. A cow releases more greenhouse gases than a prius electric car and how many cows, sheep, antelope, pigs etc. are there in the world.

Answer 3

I'll help a litttle,
2)a;Asteroid impact.Depending on the scale,effects could range from just a small:)amount of matter being ejected into our atmosphere,to worst actually being pushed out of our orbit.
b;Dirty space.Our planet passes though areas of space that because of matter accumulation less energy from the sun reaches us.

Answer 4

The fact that you wrote "anthropogenic" implies the former. Whether or not humans cause global warming does not change the definition of "anthropogenic"

Answer 5

very confusing aspect. lookup onto yahoo and bing. it will help!

Answer 6

I have done a research paper back in May on Global warming w/ sources and put it on my 360 as a reference if you want to read further

The rise of carbon dioxide is more poisonous to our atmosphere and our oceans than we may realize. The carbon dioxide from human activities causes a greenhouse gas which induces global warming, so if this greenhouse gas continues to rise, the oceans will become so acidic it could drastically threaten marine life by the year 2100. In the past two hundred years the Earth has absorbed about one third of the carbon dioxide caused by human activity. However, the rate now of the earth’s absorption of the carbon dioxide is at about one half. Faster carbon dioxide emissions overwhelm the capacity of land and ocean to absorb carbon. (Sanders) The rate of the emissions of carbon dioxide needs to be reduced in order to slow down global warming. However, there a few solutions to this problem for example, injecting the carbon dioxide into the ocean floor to absorb the carbon.

Some examples of the causes of the carbon dioxide rising are the following: fossil fuel combustion, cement manufacturing, Coal-burning power plants, Freon, industrial revolution etc. How does carbon dioxide cause global warming?

Greenhouse gases alter the situation because of their peculiar absorptive properties. The sun’s radiation arrives mostly in the form of visible light, which greenhouse gases allow to pass freely.

Coffaro 2

The earth’s radiation, meanwhile, is emitted mostly in the infrared part of the spectrum. Greenhouse gases absorb infrared radiation and then reemit it—some out toward space and some back toward earth. The process of absorption and reemission has the effect of limiting the outward flow of energy; as a result, the earth’s surface and lower atmosphere have to be that much warmer before the planet can radiate out the necessary two hundred and thirty-five watts per square metre. The presence of greenhouse gases is what largely accounts for the fact that the average global temperature, instead of zero, is actually a far more comfortable fifty-seven degrees. (Kolbert)

The rate of the increasing carbon dioxide is almost catastrophic to our atmosphere and our oceans. Elizabeth Kolbert has stated in her article, “The Climate of Man—I,” ‘Scientists at NASA have calculated the throughout the 1990s the ice sheet, despite some thickening at the center, there were also shrinking by twelve cubic miles per year.’ (Kolbert) She has also stated that in the summer of 1996, the ice around the Swiss Camp moved at the rate of thirteen inches per day, but by 2001 it increased, not decreased, to twenty inches per day. Over the last hundred years the waters risen by about a half a foot globally, and will continue to rise anywhere from four inches to three feet by the year 2100. (Kolbert) In the summer of 2002, Kolbert stated that the satellite images taken by NASA showed that the ice on the Swiss Camp melted up to an elevation of six thousand five hundred feet. By 2003, she states that an additional five feet of ice was lost. People ask where this global warming is.

Coffaro 3

In the air temperature, the signal is very small compared to noise. What permafrost, soil or rock that remains below 0°C throughout the year, does is it works as a low-pass filter. That’s why we can see trends much easier in permafrost temperatures than we can see them in atmosphere temperatures. In most parts of Alaska, the permafrost has warmed by three degrees since the early 1980s. In some parts of the state, it has warmed by almost six degrees. One of the risks of rising temperatures is that under the right conditions, organic material that has been frozen for millennia will break down, giving off carbon dioxide or methane, which is even more powerful than greenhouse gas. In some parts of the artic, this is already happening. Kolbert says that while we are waiting for evidence of global warming: we may not be given a warning until the carbon dioxide is so saturated that a significant climate change is unavoidable. By 2080 is predicted that the perennial sea-ice cover will totally disappear.


The ice and atmosphere are not the only things that are going to suffer during this drastic change in the climate. This will also significantly put a negative change to our oceans as well. Naturally when this happens the saltwater organisms will eventually diminish, because saltwater organisms cannot survive in fresh water. The North Atlantic Ocean has become fresher due to melting glaciers and increased precipitation since the 1960s both associated with global warming. Also has enhanced continental runoff due to rising waters in artic and sub-artic seas. (Caldeira)

Coffaro 4

The pH (potential of Hydrogen) scale is from 1 to 14, with 7 being neutral. Anything that lowers pH makes the solution more acidic. The scientists calculated that over the past 200 years, the pH of the surface seawater has declined by 0.1 units, which is a 30% increase in hydrogen ions. If an emission of CO2 continues to rise as predicted by the intergovernmental Panel on Climate Chang’s IS92a scenario, there will be another drop in pH by .5 units by year 2100, a level that has not existed in the oceans for many millions of years. In addition, the changes in the ocean’s chemistry will reduce the ability to absorb CO2 from the atmosphere, which in turn will accelerate the rate of global warming. (Caldeira)

As the oceans become more acidic, this makes it hard for living organisms to thrive. The ocean pH balance becomes more corrosive to shell organisms such as coral and can interfere with their oxygen supply. This could have a negative impact on calcified creatures such as phytoplankton and zooplankton, which are some of the most important players in the oceanic earth’s food chain.

Other major issues we will have to deal with would be the erratic weather changes. There would be more droughts because naturally the weather would be much hotter with this greenhouse effect. The storms would be much more violent and would be additional precipitation because of the increased evaporation of the waters.

Despite all of the radical changes happening in the earth’s atmosphere and oceans

Coffaro 5

due to the greenhouse effect, scientists hunt to find a solution for the carbon dioxide problem. Scientists tried to fertilize phytoplankton to help solve the carbon dioxide problem in two parts of the ocean but there was no significant change made.

Scientists have quantified the transport of carbon from surface waters to the deep ocean in response to fertilizing the ocean with iron, an essential nutrient for marine plants, or phytoplankton. Prior work suggested that in some ocean regions, marine phytoplankton grow faster with addition to iron, thus taken up more carbon dioxide. However, until now, no one has been able to accurately quantify how much of the carbon in these plants is removed from the ocean. New data, reported in the journal Science, suggests that there is a link between iron fertilization and enhanced carbon flux and hence atmospheric carbon dioxide levels, but the quantities that can be removed are no greater than that of natural plankton. (Fertilization)

Other solutions that scientists are experimenting with are that they are going to try to bury the carbon dioxide deep underneath the ocean floor. When you inject the carbon under the ocean floor, the carbon dioxide will want to sink, not rise, so it will stay there forever, geologically speaking, or for millions of years at least. Under thousands of feet the carbon will be cold, compressed, and heavier than the water. (Scientists) Unfortunately though, the carbon burial would not work everywhere. In some areas it would be too expensive to have so much carbon buried into the ocean floor.

Coffaro 6

As a result of the issue of the carbon dioxide turning our oceans into acid and melting away our polar ice caps, we need to continue to hunt for ways to not speed up the process of the global warming. If we continue to pollute the air with carbon dioxide many creatures will suffer and others will go extinct. Our weather would be horrendous and global warming as a whole will be a drastic and catastrophic change we couldn’t even imagine what we may to have to live in. It may be a never-ending battle before people will realize that global warming is real and that the scientists who study this are in a constant hunt for the final solution to this problem.

some really good sources on this... Elizabeth Kolbert is one of my favorite scientists on this subject and Ken Caldeira is also good.
http://lwf.ncdc.noaa.gov/oa/climate/globalwarming.html#Q11
http://www.newyorker.com/archive/2005/04/25/050425fa_fact3
http://www.wesjones.com/climate1.htm
http://www.livescience.com/environment/050630_oceans_acid.html