ICE is water frozen into a solid state. About 1.7% of the Earth’s fresh water is trapped in glaciers and the ice caps of Antarctica and Greenland. Ice stops the decaying process and could preserve biodegradable matters for a long time and even for a lifetime. This is the reason why we freeze our food like fish and meat.
Remember Ötzi the Iceman? The famous ice mummy found on the mountain border between Austria and Italy in 1991. Otzi lived 5,300-years ago. Because his body was frozen, scientists were able to determine not only the cause of death, but even the last meal he ate. Much of his clothing and possessions are also intact.
Now, scientists are turning to ice to study pollution levels long time ago. Air pollutants that fell on glaciers are buried in time and preserved. Ice samples are drilled deep into glaciers to study what was pollution like in the olden times. It is much cheaper to test ice cores, which capture years of data in one core, than to do repeated air sampling over time according to scientists.
One recent study that was published in the journal Science Advances this March 2015 was on the effects of leaded gasoline in the environment. The analysis of the ice cores found that leaded gasoline was a larger emission source of the toxic heavy metal lead than mining in South America. Researchers made the measurements in an ice core from a Bolivian glacier.
The study highlighted the importance of the ban on leaded gasoline for the environment and human health. If inhaled, lead can enter the bloodstream and ultimately the brain, where it poisons nerve cells. It’s a good thing leaded gasoline was banned in the Philippines in 2000 in accordance with the provisions of Republic Act 8749 otherwise known as the Clean Air Act of 1999.
Again in South America, ice cores were used to determine the extent of pollution from as far back as the 16th century. The ice core provided the first detailed record of widespread human-produced air pollution in South America before the industrial revolution. The pollution came from the processing of Silver from the mountaintop mines of Potosí, in what is now Bolivia, which was then the largest source of silver in the world.
In the Tibetan Himalayas, Lancaster University scientists worked with scientists from China and Germany to collect and analyze samples from ice cores which had been laid down over 30 years, to show how residues of Perfluoroalkyl substances (PFASs) in the environment have changed over time. PFASs are used in many everyday products such as fabric linings, non-stick pans and fire extinguishers.
The results show decreasing concentration of the pollutant over time which coincides with an international agreement on phasing out the use of these toxic persistent organic pollutants. This shows the effectiveness of joint efforts to address pollution. This research paper was published in the leading American Chemical Society journal, Environmental Science & Technology.
Scientists are also drilling and analyzing ice cores is to find out levels of carbon dioxide in the atmosphere at different points in Earth’s history as well as recording temperature. Air bubbles remain trapped in the ice. Scientists use these to find out the concentration of greenhouse gases like carbon dioxide and methane.