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Presented on the third conference of The High Panel on Water and Peace”,
December 7-9 2016 – San Jose, Costa Rica

by Andres Tarand

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The main sources of the presentation are Scientific journals The Cryosphere (2016), Nature (2016), Science (2014, 2015).


The aim of this presentation is to offer latest scientific achievements and conclusions on the development of the Earth Cryosphere[1] in polar regions. It does not include alpine glaciers, which have been mankind´s water suppliers for centuries and are now monitored by the UN-Water or national governments.

Let us start from the Arctic where the ice sheets have entered a phase of dangerous instability.

Greenland`s continental glacier

The melting and crushing of ice has been accelerated at least in the last three years (NASA monitoring). The main reason seems to be not so much the warming of the atmosphere and ocean but soot emitted during industrial period in Europe and North-America. Soot does not reflect solar radiation like does snow and its particles intrusion spoils the ice structure. It is interesting to note that in the early fifties of the last century Soviet academician M. Budyko proposed in the framework of “Great Plan of Stalin on Reshaping the Nature” to seed the soot from airplanes onto the Arctic Ocean ice for better shipping routes. The plan was not implemented then but is realized now via “international efforts” in Greenland.

Arctic Ocean ice

After significant decrease of the ice area on the Arctic Ocean in summertime from the beginning of this millennium the discussion about Arctic turned too political. Not only the member states of the Arctic Council but also superpowers like China or EU demonstrated their interest toward energy resources of Arctic basin or for new shipping routes. Russian experiments for starting oil or gas production failed because of ice presents in wintertime. The issue about ice free Arctic in winter is scientifically not finally solved. But thanks to NASA monitoring during the last 30 years we know now what happens to the sea-ice in summer. Arctic sea ice structure has been very variable due to tides, currents, waves, winds, snowstorms etc., which all produce different thickness of ice. The most resistant to melting have been blocks with the age of three-four years (3-4 m thick). The one year old ones have thickness 1–2 m. Thirty years ago, share of thick blocks was 20 %, now it makes up only 3% from the total sea ice in Arctic. That could lead to summer-ice free Arctic in the near future.

Permafrost melting and emission of greenhouse gases

In spring 2016, the results of a twenty-year long research of Tomsk State University (Russia) were published. The area of investigation covers West-Siberia where permafrost melting has caused the appearance many (millions of) small lakes. The size of local wetlands surpasses those of Scandinavia, Canada, and Alaska as well as East-Siberia. All these lakes are sources of carbon dioxide, which is product of decomposing peat. Theoretically, that process was forecasted years ago, but within a few last years the process is accelerating.

The same Tomsk University research group discovered on the West-Siberian shelf area massive methane emission. Now, more papers are published about methane lenses on the seabed of the Norwegian and Barents Seas. The last ones are defined as relicts of the last Scandinavian Sheet about 10 thousand years ago. Since the findings are quite fresh it is difficult to say something about their emission capability into the atmosphere but anyway the probability of more GHG[2] emission seems most likely.

The West-Antarctic Ice Sheet

Most of the West-Antarctic ice is sitting on the bedrock hundreds or thousands of meters below sea level. Only three years ago, by the estimation of the Intergovernmental Panel on Climate Change (IPCC) the average sea-level was rising more due to Greenland´s ice-melting than caused by West-Antarctic ice. Now the share of these glaciers in effect to the sea level could be opposite. The reason was discovered recently – warming oceans are attacking the West-Antarctic sheet from beneath destructing foundation and accelerating the production of icebergs. Calculations of the global mean of the sea level show that West-Antarctic melting had a significant role also on the last inter-glacial period (115 000 – 130 000 years ago), when the mean sea level was 6–9 meters higher.

Ice-melting processes that were shortly described above combined with growing concentration of the greenhouse gases in atmosphere tell us of more intense processes of climate change. That is backed also with data about the rise of the mean sea level (often the main argument for journalists describing climate change). The average growth of the global sea level during the 20th century was 1.7 mm/ per year; in 1989–2000 2.8 mm/per year; 2000–2010 3.1 mm/per year and now is 3.3 mm/per year. For us probably more important is the proportional rise of the sea and the loss of global freshwater resources, which opposes the growing water scarcity.

To finish this short observation positively we should add good news from the East – Antarctic Ice Sheet, which contains 90% of the freshwater of all glaciers. Remember that total amount of the global freshwater is 90% contained in ice. Scientific expeditions to the Antarctic began a bit more than hundred years ago, and the intense international cooperation was started with the Second Geophysical Year in 1958. Both, the quality and quantity of researches was growing during these 60 years but calculating the balance of ice in the East-Antarctic has been an exception. There are many reasons for that but the biggest puzzle has been the measuring of precipitation and especially flying snow in snowstorms. Latest calculations have had a trend to conclude that the East-Antarctic Ice Sheet is slightly accumulating snow, which thus turns into firn and ice. But then there are many reasons to doubt today’s ice balance calculations. In 2016 results of the ice drilling in the East-Antarctic were published, which describe the climate in terms of air temperature and concentration of GHG during the last 740 000 years i.e. covering almost half the time of the Homo sapiens existence on the Earth. In the context with global freshwater resources it is pleasing to know that the East- Antarctic Ice Sheet never disappeared (melted). Technology that is needed for the use of that freshwater resource is quite a different story…

[1] The cryosphere is the frozen water part of the Earth system. Beaufort Sea, north of Alaska. One part of the cryosphere is ice that is found in water. This includes frozen parts of the ocean, such as waters surrounding Antarctica and the Arctic. There are places on Earth that are so cold that water is frozen solid.

[2] (GHG) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in Earth’s atmosphere are water vapor, carbon dioxide, methane, nitrous oxide (the laughing gas), and ozone.

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