The world in 1998 was subject to increasing stress from natural forces, war and disease. But there were some more hopeful developments as well.

The Worldwatch Institute, an environmental research group based in Washington DC, says last year was in some respects a record breaker.

In Vital Signs 1999: The Environmental Trends that are Shaping our Future, the Institute says last year's record average global temperature "literally went off the top of the chart we have been using for years".

Costly weather

The unprecedented warmth caused more evaporation and rainfall than usual and provoked more destructive storms.

Weather-related damage worldwide totalled $92 billion, 53% more than the previous record, the $60 bn recorded in 1996.

Storms and floods meant that at least 300 million people had to leave their homes, many of them in China's Yangtze River valley, eastern India, and Bangladesh.

Smaller numbers were affected in the Caribbean and central America by two of the most powerful hurricanes ever known, Georges and Mitch.

Slow growth

Sperm count falling

The Institute's report says the rate of global economic growth declined from 4.2% in 1997 to 2.2% last year, the slowest rate in seven years.

For the first time in 15 years, there was a drop in 1998 in international trade, down by 4%.

The report identifies an increased readiness to resort to armed conflict: "After five annual declines, the number of wars in the world climbed from 25 to 31 in 1998. Nearly all were internal or civil wars in the developing world."

In late 1998 world grain prices fell to their lowest level in 20 years, partly because of East Asia's economic downturn, "but more fundamentally because of extensive overpumping for irrigation in both China and India".

"In effect, both countries are expanding food production in the short run by depleting their aquifers, which means they will face sharp cutbacks in irrigation water supplies once the aquifers are depleted."

Net spreads its tentacles

But China also showed "some of the most explosive growth" in the use of the Internet, where the number of users last year doubled to 1.6 m.

"The number of lines linking host computers to the Internet increased to 43 m in 1998, up from 30 m the previous year ... 147 m people worldwide now have access."

The year saw cigarette production per person fall by 2%, continuing a decade-long trend. Production peaked in 1990, but since then has fallen by almost 8%.

The report says the number of HIV cases last year totalled nearly 6 m, and deaths 2.5 m. And it identifies what it calls "another sign of deteriorating human health" - a fall in sperm counts.

In US men, the average count per millilitre of semen has fallen from 120 m in 1940 to just under 50 m in 1998. The trend in Europe is similar.

The Institute says the principal explanation is endocrine disruption, the process by which chemicals found in plastics, pesticides and industrial pollutants mimic the female hormone oestrogen.