Cities especially modify their own climate. Narrow confined streets obstruct and deflect the wind, houses and pavements absorb radiation and the issue of hot air from houses, furnaces and restaurants generally cause towns to have temperatures a few degrees higher than the surrounding country. Snow goes to slush under the wheels of the traffic and is swept away or melted down the gutter. But perhaps the most important feature of the urban climate is its degree of atmospheric pollution from domestic chimneys, from factories, from chemical industries, from gasworks.
Meanwhile it reduces the sunshine, absorbs the sun's rays, checks the escape of heat like a glasshouse, smothers the grass, blights the miserable trees and does immeasurable harm to the health of the town-dweller. When we consider how many of our climatological stations are urban it would seem likely that they give a slightly distorted statement of our climate, flattering the town perhaps at least as far as temperature is concerned but depressing the sunshine figures. But then most of our population is urban and spends its holidays by the sea.
Man's reaction to the climate is as variable as his physique or his purse allows. Refrigerators are in increasing use but there are few who find it worth while to cool their houses by air-conditioning, preferring to open the windows to bring in the air-temperature of outdoors, which is cool enough. Some heating is needed for at least six months of the year and now techniques of central heating by oil or solid fuel are making good progress, aiming at temperatures in the sixties rather than, as in America, in the seventies. More could be done in this direction, not only against winter chill but also against damp which is damaging; there is no doubt that Britain's climate, especially in winter, is everywhere too humid for good health and rheumatic diseases are too common.
It is worth while to remember that Britain's climatic network, its professional observers supplemented by a host of volunteers, is one of the closest in the world and reaches the highest degree of accuracy. The Meteorological Office, a department of the Air Ministry, supplies the press and the B.B.C. with weather forecasts, gale, frost, fog and snow warnings and with regular shipping forecasts. Its organization includes a climatological branch with a huge reservoir of statistical data for the whole world. Information is available for farmers, gardeners, town- and country-planners and geographers of all kinds and interests on those matters that concern the atmosphere and its ways.