for better research go to under NOAA - Climate.gov
This is a short paraphrased summary of the article about ice cores in that website.
Answer: Researchers in labs may melt or crush bits of the ice core a little at a time, each deeper layer shows the time in the Earth's climate history. Tiny pieces of pollution, metals, radoiactive fallout, pebbles, sea salt, volcanic ash and even air bubbles all present important information that researchers can look for to track changes in the atmosphere's composition and temperature.
<span>The
higher the altitude, the lower the atmospheric pressure. Lower pressure
in turn causes water to evaporate more quickly, and water actually
boils at a lower temperature. The percentage of oxygen in the air at two
miles (3.2 km.) is the same as at sea level (21%). However, the air
pressure is 30% lower at the higher altitude due to the fact that the
atmosphere is less dense--that is, the air molecules are farther apart.
The important effect of this decrease in pressure is this: in a given
volume of air, there are fewer molecules present. This is really just
another way of saying that the pressure is lower. This is called Boyle's
law.</span>
here is the answer
the percentage on population trends is 0.2%
The population is decreasing due to low birthrates and high death rates.
It is difficult to make generalizations about the highland climate zone because little research has been done at high altitudes, and data is not readily available. Without actual data, it would be wrong to make any generalization about the highland climate zone.
Hope this helps
