It has been 42 years since an American president set foot in Quebec. But it took only two hours for President Reagan and Canadian Prime Minister Brian Mulroney to reach an agreement this past weekend in Quebec on what Canada now considers the most pressing issue with its southern neighbor: acid rain. Experts here say the speed of the agreement owes partly to a warming trend in relations between the two countries, a trend that has been hastened by the personal and political affinity between the two conservative leaders. It also stems from the fact that both sides have agreed, in effect, to postpone hard politicial choices raised by the acid-rain issue by assigning it to a study commission.
This week's agreement, which calls for special envoys to examine the issue, is ``mostly symbolic,'' says Joel Sokolsky, a political scientist at Dalhousie University in Halifax, Nova Scotia.
``But it does raise expectations, and it commits Reagan publicly to a high level of interest in the acid rain question,'' says Mr. Sokolsky.
``Acid rain'' is the name given to natural precipitation that has mixed with sulfur dioxide, nitrogen oxide, and other chemical air pollutants, and become acidic. It is accused of killing trees, sterilizing lakes, and pitting buildings in eastern North America and parts of Europe.
The US and Canada have argued about acid rain for years. In essence, Canadians complain that their environment is being damaged by pollution exported from the US. Twenty percent of Eastern Canada's 50,000 lakes are thought to be acid-damaged. Half the offending acid deposition is caused by US burning of fossil fuel, particularly in Ohio River Valley power plants, claim Canadian officials.
The Reagan administration, in turn, says acid rain is an issue not well understood, and that expensive, and perhaps misguided, cleanup programs should be avoided.
Acid rain is a major issue in Canada, as the industries at risk (tourism, fishing, agriculture) account for almost 10 percent of the nation's gross national product. Last week, the Mulroney government announced plans to cut Canada's own sulfur-dioxide emissions in half within 10 years.
But US governments have failed to address the problem with consistent urgency. Recent scientific study on the causes and effects of acid rain suggest it is caused by many pollutants: nitrous oxides and hydrocarbons from automobiles, ozone, lead, and other heavy metals, as well as sulfur dioxide. The Reagan administration has therefore doubled spending to study acid rain but refused to spend money on any cleanup programs.
A previous US-Canadian acid-rain concord, signed in 1980, has led to much research but no specific pollution renduction steps.
Reagan and Mulroney also agreed to modernize their jointly maintained air defense system. The so-called Distant Early Warning System, which was built during the 1950s, was designed to guard against Soviet bombers flying over the North Pole. Under the terms of the new agreement, the US and Canada will commit $5 billion to 52 new manned and unmanned radar stations -- renamed the North Warning System -- to plug holes in the aging system to make it effective against low-flying Soviet bombers and cruise missles.
[In an interview on Canadian television during the Reagan visit, reported by the Associated Press, US Defense Secretary Caspar Weinberger said the US and Canada may develop a joint defense against Soviet cruise missiles that could entail placing antimissile missiles in Canada as well as in the US or at sea. Reagan spokesman Larry Speakes later stressed ``any deployment of any missile-defense system would be a Canadian decision.'']
Experts here say the two agreements reached at Quebec -- plus a third on Pacific salmon fishing -- underscore an improving trend in US-Canadian relations that began during the last year of the Labor government of Pierre Trudeau. Before then, Canadian efforts to secure controlling interests in its domestic oil and gas industries -- often at the expense of US investors -- plus the imposition of more stringent controls over US investment generally, triggered US protests and threats of economic retaliation.
Now, with unemployment high in Canada and with the Canadian oil and gas industry on the ropes because of falling oil prices, Canada is more actively encouraging US investment, even as the Ottawa government is seeking to expand trade relations with the US. Likewise, Mulroney has been a more outspoken supporter of the Reagan administration's defense policies, including the President's proposed new Strategic Defense Initiative.
Correspondent Peter Grier also contributed to this article.