As Mark Twain is to have remarked, everybody talks about the weather but no one does anthing about. Just now proposals are in the wind, with heat and drought uppermost in people's minds, that could at least make long-range weather prediction more of a science and less of a guessing game.

The House is about to cosider a bill, with every likelihood of passage, that would pull together all the widely scattered governmental funcitons concerned with weather. The bill's sponsor, Rep. George E. Brown Jr. (D-Calif.), believes that this coordination will make it possible to monitor long-range trends for prediction three monghs in advance of possible radical changes in weather patterns.

For example, the exceptional cold of last winter might have been predicted if research had been coordinated to make clear the shifts in the upper atmosphere and their significance. With advance prediction, steps could have been taken to mitigate the worst consequences of the cold.

Similarly, the prolonged drought in the West might have been anticipated by a three-month prediction at the outset, showing the shifting patterns in the upper atmosphere over the Pacific. This might have obviated hastily improvised measures and made possible a long-term program equaliziang the hard-ships of the most stricken areas and those not so hard hit.

In the forefront of concern is how much man has contributed to damaging the environment, thereby opening the way to radical changes in the weather. The National Academy of Sciences is completing a voluminous report on the concentration of carbon monoxide that helps to generate the smog hanging over urban areas. According to those who have seen advance copies of the summary of what will be a four-volume study, principal offenders are the automobile exhaust and the smokestacks of industry that burn oil and natural gas.

Changing over to coal, as President Carter has recommended, would create even more serious atmospheric hazards. Coal in combustion releases uflfur dioxide gas and sulfate particles. In haling these can cause respiratory diseases sihc as emphysema and, by one estimate, shorten the life span by as much as 15 years.

The concern is worldwide. A leading climatologist, Eugene Bierly of the National Science Foundation, has just returned from a seminar on climate held in Leningrad. The chief of the Soviet delegation, Prof. Mikehil Budyko, also a noted climatologist, believes that manmade custs and gases are almost entirely responsible for extremes of weather occurring around the world. While the number of privately owned cars is small as compared with the U.S., smog has developed in Moscow in the past two or three years with a heavy charge of carbon monoxide.

Factors of which we are often blithely unaware are credited with changes in the atmosphere and therefore in the weather. One is the destruction of jungle vegetation. AN example is Brazil, where vast forests have been wiped out in the Amazon basin by the slash-and-burn method in a drive to create farm land.

Bierly talks about the naive assumption that the climate is bound to be benign with only occasional temporary aberrations. On the contrary, with the population explosion forcing an ever more persistent drive for food - as in the Amazon basin - the climate is likely to be ever less benign.

One concern of the climatologists is the overheating ofa the earth's atmosphere due, in no small part, to the release of thousands of tons of carbon dioxide. What this can mean to the polar icecap has long been a foremost concern of those who follow the long term trends of climatic change. If the melting of the ice cap is accelerated, the consequences in rising ocean tides could be disastrous. On the Eastern seaboard it could mean wiping out ports and even port cities.

Talking about the heat, the humidity and the water shortage, which has now reached the parched East Coast, is a preoccupation in this torrid summer.

At least it helps to relieve the emotions. Even more deserving of discussion - and exploration - is the question of whether advance predictions could have any useful effect.