Brussels — The North Atlantic Alliance for the first time in its more than 30 years of existence has published a comparison of Western and Warsaw Pact forces that shows the Eastern bloc having a quantitative edge in most military areas with the exception of several naval equipment categories.
The alliance document, which has been the subject of intense internal discussion for several months, was issued May 4 at NATO headquarters. Its release comes in the midst of massive debates and controversies throughout the alliance countries over defense and nuclear strategy and spending.
NATO Secretary-General Joseph Luns, in introducing the study, remarked that the comparisons ''do not make comfortable reading.''
But he added that despite the numerical superiority of the Warsaw Pact in a number of fields, ''we are still in a position to have a credible'' deterrent. General Luns also commented that in his opinion, the main area of Western deficiency lay in intermediate-range nuclear missiles, which NATO's controversial 1979 missile deployment decision is aimed at remedying.
Ironically, it is in this area that the NATO study disagrees with Reagan administration assertions about the size of this missile gap.
While American officials for months have been contending that the Soviet Union had a 6-to-1 edge in such European theater missiles and aircraft, the NATO survey puts the difference at 4-to-1. The NATO survey includes additional British aircraft and counts fewer Soviet missiles.
For the most part, the numbers of troops and weapons systems cited in the NATO study are similar to those contained in reports by Western research institutes. It shows the Warsaw Pact ahead in most categories of troops, aircraft, and missile systems. It gives NATO a lead in a number of maritime systems, although it adds that this advantage is insufficient to assure NATO's superiority at sea.
The result is a study that is limited to a statistical comparison of tanks, aircraft, missiles, and other forces but that makes no attempt to evaluate more abstract characteristics such as survivability, efficiency, or general technical quality or advantage. It also does not consider reserve forces, American and Canadian or British forces not on the European continent.
And perhaps of major importance in the actual balance of forces, the NATO study does not include any French forces, which are not technically part of the alliance military structure, or Spanish forces, which do not officially join NATO until next month.
The study's introduction does note that various differences, such as the geographic unity of the Warsaw Pact, can benefit performance in such fields as reinforcements, whereas NATO reinforcements could have to cross the Atlantic Ocean. On the other hand, Warsaw Pact naval forces have a geographic handicap of having to navigate through ''choke points'' around the North Cape of Norway, the Baltic Sea, or the Turkish straits, all defended by NATO forces.
In a number of areas, however, the NATO study appears to be incomplete. In the important area of tank warfare, for instance, the report refers to ''a very unfavorable ratio between NATO antitank guided weapons and Warsaw Pact tanks and armored personnel vehicles.''
The statistics cite some 8,000 NATO antitank weapons in this balance. But the Alliance has had a program under way for several years to add some 40,000 antitank weapons to bridge this gap.
In addition, the report notes that while the Warsaw Pact countries devote an estimated 11 percent of their combined gross national product to military spending, the NATO countries allocate only some 5 percent of their total output. Other Western and NATO statistics, however, show that because of the much larger Western industrialized economies, the NATO countries probably surpass the Eastern bloc in total defense spending.