North Gets Warmer

It has been noticed that the climate inthe northern areas of the Earth is growing warmer. The average annual temperature in Spitsbergen has gone up by 12'C and in Greenland by 7'C. There are areas in Alaska and Scandinavia which were covered with ice several years ago, but are ice-free now. Why is this so?

There are two hypotheses. One says that the warming up process is produced by the formation of a new branch of the Gulf Stream. The other connects the warming upwith industrialisation. Factories discharge colossal amounts of carbon dioxide into the atmosphere. Even sma11 amounts of this gas in the atmosphere (0.03 per cent) act as a thermoregulator.

4. "Green revolution"

Scientific and technological progress is making itself felt more and more in agricultural production of the developing countries. It is not only by way of improving farm machines and implements, of more effective chemical fertilisers to the farmer, but also of progress in selection and genetics, what is called in the West "green revolution". The first problem which scientists want to solve is the problem of "straw-grain" balance. It is not good when the biggest part of the plant food from the soil goes not into the grain but into the straw. Now it is known that too muck fertiliser adds height to the plant, which is not what the grower primarily wants. Tall stands of grain are easier beaten down by wind and rain and this only makes harvesting more difficult.

Looking for the solution of the problem selectionists focussed attention on "dwarf" varieties of wheat. As a result the new varieties were deve1oped in Mexico, which solved the grain problem there. They proved to bethree times more productive than ordinary varieties, and adapted themselves very well to the conditions of tropical and subtropical areas where because of short day1ight hours wheat does not grow well. Mexico stopped importing grain and since the mid-sixties has herself been exporting about a million tons annually.

Many countries, primarily those of tropical Asia, took an interest in the new varieties, In the course of 3-4 years, the hybrid wheats became a leading grain crop in this area. In India the "Mexican" varieties, further improved by local selectionists, were planted over an area of 4,000,000 hectares.

Scientists now turned their attention to another cereal that has been the main food for centuries – rice. In 1962 an International Rice Research Institute was founded on the Philippines. The local climate, in which three harvests a year can be grown, made it possible to carry on selection work very quick1y. By 1965 two dwarf varieties of rice grew on farm fields. Besides doubling and trebling the yields, they matured a month earlier than the usual varieties of rice. Later, sti11 more rapidly maturing hybrid was grown which requires only 90 days from planting to harvesting instead of the 140-180 days for ordinary varieties.

Selectionists working with maize and millet also succeeded in increasing yields.

The developing countries have worked at the problem with energy. In the United States it took 15 years to get а hybrid maize evolved into large-scale cultivation. The scientists of young developing countries themselves have contributed very much to the further improvement of imported varieties. In India, for instance, wheats with heightened immunity to plant diseases and highest protein content were obtained in the period of five years on the country's farm fields.

Here are some of the initia1 (first) results of the "green revolution". Some developing countries already are close to being able to meet their own grain requirements.