LAST month, Hurricane Bob visited the North American East Coast. Volcanic ash threatened Mt. Pinatubo's neighborhood in the Philippines. Earthquakes shook various parts of the world.This summer, like all summers, has its share of rough weather and geological upheavals with attendant human impact. But in this decade of the 1990s, unlike other decades, the world community is challenging itself to curb the disasters. It's the International Decade for Natural Disaster Reduction - authorized by the United Nations General Assembly in 1987 and endorsed in 1988 by the United States Congress. The US National Academy of Sciences sets out that challenge in a recent report. It says, in essence, that, while nature may continue to rampage, disasters are man-made. They can be reduced. Unwise land use - such as populating flood plains, fault zones, or volcanic slopes - puts people needlessly at risk. Shoddy building practices make foolishly unsafe structures. Lack of adequate warning and of emergency response plans often adds more unnecessary danger. It has become a cliche to note this. But cliche or not, the world can't go on living this way. According to a World Health Organization estimate, almost 2.5 million people died and 750 million suffered injury in natural disasters around the world from 1964 through 1983. That's mild compared with what might - but need not - happen in the future. In releasing its report, the academy noted that "as populations increase and concentrate in vulnerable urban and coastal areas, the toll of natural disasters can only be expected to increase unless concrete and immediate actions are taken." Richard E. Hallgren, executive director of the American Meteorological Society and a member of the academy's report committee, says that "reducing the impacts of natural disasters will require a shift in attitude." He explains, for example, that "people will have to be willing to accept decisions with regard to land use and invest in buildings that are hazard resistant." And, he adds, "policymakers have to support these changes." This is the biggest challenge of all. How often after a major disaster do news interviews feature people who want to return to living as they did in a dangerous area? How often do development interests resist sound land-use restrictions? And how often do politicians avoid enacting such restrictions as well as safe building codes? The global record is spotty with some communities being better prepared than others. However, the academy report makes it clear that all communities could do more to firm up their acts. The report proposes a program for doing this. It includes such measures as fully assessing natural hazards and identifying ways to mitigate them. That means tougher land-use and building codes. The report says it's possible substantially to improve forecasting and warning. It recommends extensive international information exchange. Such measures have been proposed before. They would seem to be matters of common sense about common safety. Yet, because they involve a change of mind-set regarding how people live on this vigorously active planet, they often are ignored. It's time to wise up to safer living.