PTI
 
New York, Dec 16: The current year is expected to go down in history as the sixth warmest year on record with prolonged drought in some regions, heavy rainfall and flooding in others and deadly typhoons in south east Asia.

But the human-induced global warming may not be the culprit with mischief being done by rising concentration of human populations and increasing infrastructure in the coastal region, scientists say.

The global mean surface temperature is currently estimated by the World Meteorological Organisation (WMO) to be 0.42 Celsius above the 1961-1990 annual average of 14C.

Many UN officials, agencies and reports blame human role in producing the greenhouse gases for global warming and the UN-backed Kyoto Protocol seeks to significantly reduce such emissions.

But just this week the WMO reported that no firm link can yet be drawn between human-induced climate change and variations in intensity and frequency of tropical cyclones.

The year also continues the pattern of sharply decreasing Arctic sea ice, with the September rate declining by some 8.59 per cent every decade, or 60,421 square kilometers per year.

The agency will not release final figures for 2006 until March, but preliminary findings show that, averaged separately, temperatures for the northern hemisphere (0.58C above a 30-year mean of 14.6C) are likely to be the fourth warmest and for the southern hemisphere (0.26C above a 30-year mean of 13.4C/56.12F) the seventh warmest in the instrumental record from 1861.