There was a great article on the global importance of ice in Nature earlier this year that I only just stumbled across today… According to Thorsten Bartels-Rausch:
“Ice is central to climate, geology and life. Understanding the behaviour is essential for predicting the future of our planet and unravelling the emergence of life in the Universe. Water ice frosts planets, moons and comets in our Solar System. On Earth, white polar ice caps reflect up to 90% of the Sun’s incoming radiation. On average, 7% of the ocean’s surface is frozen; sea ice alters ocean currents and limits the exchange of gases with seawater. Ice and snow coat 10% of the land permanently and up to half of the Northern Hemisphere in midwinter. These blankets of frozen water insulate the ground and the oceans.
“Ice clouds concentrate airborne chemicals and are sites for atmospheric chemistry. Above the poles, clouds of ice grains host ozone-depleting reactions, forming holes in the stratospheric ozone layer at high latitudes that expose millions of people to increased ultraviolet radiation. Chemical reactions in snow on the ground can produce ozone and other environmental pollutants. Organic toxins and mercury accumulate in snow and can be released into rivers and oceans when the snow melts, where they enter the food web.
“Yet the molecular mechanisms underlying these processes remain largely unknown. Without knowing more about how chemical reactions proceed in ice and snow, and where they occur within the grain and crystal structure, it is impossible to build snow or ice-cloud models or to extrapolate laboratory studies to environmental conditions with enough confidence.” (p.27)
“In my view,” he continues, “the chemistry and physics of ice need to be studied more on a molecular scale if we are to address the massive environmental problems we face. Recent advances in computer simulations and in experimental techniques such as surface-sensitive spectroscopy, which can now be operated at temperatures and pressures [-p.28] relevant to ice in the environment, open the door to exciting future studies. Here, I summarize ten open questions about ice.” (pp.27-28)
These questions (which are each accompanied by a paragraph of interesting discussion) are:
How does ice form?
How does ice structure change?
How do different ice structures behave?
What is the surface structure of ice?
Where do impurities lie within ice?
How do reactions proceed in ice?
Are there pockets of liquid in ice?
How do physical processes affect ice impurities?
How does ice growth affect impurities?
How long will ice last?
I recommend this article to anyone, but a special note to science teachers teaching mass spectroscopy for NCEA now – the potential of spectroscopic techniques for answering these questions is something Bartels-Rausch points to a few times and this article may offer insight into the topic….
Ref: Thorsten Bartels-Rausch (2013) Ten things we need to know about ice and snow. Nature 7th February 2013, Vol. 494, pp.27-29