Unusual Warmer Winter

By Chung Yong-seung

Some people are saying that today's winter is no colder than the winter weather of the last 20 or 30 years. The ageing process should mean that they do feel somewhat colder, but elderly people clearly do not.

Their perception is entirely right, and global warming is the reason.

In the past, there was an ice-field half a meter thick on the Han River in Seoul, and hundreds of people used to play ice hockey games and hold skating competitions on it.

The river now does not freeze up solidly in winter and if it does freeze, no one can walk on the thin ice there.

Climatologically, the global atmospheric environment has warmed by 0.6 degrees Celsius, while the minimum air temperature over the Korean Peninsula has increased by as much as 1-2.5 degree Celsius over the last 20 years.

However, the rate of air temperature increase over the hilly, mountainous and seashore areas is close to the global average.

In central Korea, there used to be two or three very cold spells each year, and the lowest air temperature during January was in the range of minus 18 to minus 24 degrees Celsius.

In contrast, in recent years we achieve only minus 10 to minus 14 degrees Celsius, and in the first 10 days of January this year the recorded minimum air temperature was only minus 7 to minus 11 degree Celsius.

In an average year, the lowest temperatures occur around Jan. 14 and continue until the beginning of February. It now appears that the lowest temperature ― down to minus 15 degrees Celsius or less ― will not happen this year.

We find the track of cold Siberian and Mongolian anticyclones has shifted north and the intensity of high-pressure centers has weakened. This produces a warmer air temperature, and global warming is the cause.

Currently, global warming is produced largely by the anthropogenic emission of greenhouse gases such as CO2, CH4, N2O and so on, and from the increased release of heat from residential areas, industries and transportation. The decrease in world forests and in tree density is another cause of global warming.

With climate warming, semi-permanent snowfalls and glaciers over alpine and Arctic environments being reduced in their size and depth.

Through the animation of daily satellite images for eight years over the Arctic Ocean, in 2002 we, together with Canadian scientists, found that the Arctic ice has been melting to more than one half of its size in July and August.

In the future Arctic seaways from East Asia to the Atlantic Ocean will be opened. Canadian scientists have also found recently that many shallow lakes across the Arctic are drying up.

The melted water and vapor are transporting to lower latitudes to increase various natural disasters including heavy rain, flooding, tidal waves and typhoons. With the northward shifting of the subtropical climate to the Korean Peninsula, the paths of intense typhoons are nearer by 300 to 400 kilometers.

There are potential pros and cons as regards the climate change. The growing season is increasing and now we do not need to rush to harvest rice crops to avoid frost and snowfall. In Canada and Russia, the farmlands are shifting to the northern lands.

The cost of heating in winter months is reduced and lighter clothing can be worn. On the other hand, bacteria and viruses survive over winter and will be spread drastically with warm and moist air to cause new diseases. Many industries, including transportation, fisheries, communication, and leisure, will be affected.

It is claimed that the negative impacts of climate change are of concern to many leaders of world communities. For example, the U.N. has declared that climate change is the top priority problem we now face this century.

Some leaders have also said that global warming and climate change are potentially more dangerous than World Wars I and II.

Presently, Korea ranks 9th in the importation of world energy resources and combustion which emits greenhouse gases and air pollutants.

Since 1990, measured concentrations of atmospheric CO2 at the western shore of the peninsula have increased from 360 ppm to 390 ppm. The country's efforts to reduce greenhouse gases, however, place Korea only 54th in the world (Germanwatch, December 2007).

Since Korea is hoping to become a developed country, now is the time to act, to produce an environmentally sound policy and reduce anthropogenic gases and climate change in the immediate future.

Chung Yong-seung is a professor at the Korea Center for Atmospheric Environment Research.