Pathanamthitta: Besides hot dry wind blowing in from Tamil Nadu, an increase in ground-level ultraviolet (UV) radiation, too, is sending the temperature soaring in Kerala.

The State's temperature is normally high during the six-month summer solstice that begins around December 22. The temperature usually remains high till the summer rain that brings respite from the scorching heat after April 14.

Several places in Kerala have been experiencing temperatures two to three degrees Celsius above normal this summer.

Experts held the cloudless, clear skies responsible for the increased intensity of ultraviolet rays, which have been scorching Kerala. Additionally, global warming, exhaust from vehicles, asphalt, concrete, environmental degradation and heat islands (formed as a result of the vegetation getting replaced by structures necessary to accommodate the growing human population), too, have been sending the temperature soaring.

UV index at dangerous level

Global satellite-based earth observation has found the UV index crossing 12 in several districts. It is a matter of concern considering the fact that European nations issue warnings if the UV index crosses seven.

The India Meteorological Department is not equipped to measure UV index. Though the Kerala State Disaster Management Authority has initiated steps in this direction, it is not yet ready to issue precise warnings.

No heat action plan yet

Kerala is yet to draw up a heat action plan, despite a demand for it from various quarters.

Workers should be restricted from outdoor activities between 11 am and 3 pm, when the UV rays are relatively stronger. The Department of Labour has directed to rest the workers during this period.

Effect of UV rays

Exposure to UV rays could initially lead to sunburn, and if preventive measures are not taken, could result in sunstroke. Researcher Dr Rajagopal Kammath opined that 'A' and 'B' types of UV rays affect humans. Kerala's proximity to the Equator is responsible for the increased UV radiation in the State.

Punalur recorded the highest day temperature of 39 degrees Celsius the other day. The night temperature, too, was high in Punalur: 19 degrees Celsius.

Threat of desertification

Experts are worried over the huge difference in the minimum and maximum temperatures, since they felt the difference of more than 10 degrees Celsius hinted at the desertification process.

Dr M G Manoj of the Cochin University said Kerala should take serious note of the difference of 20 degrees Celsius in minimum and maximum temperatures in Punalur.

Incidentally, as many as 1,600 people suffered sunstroke during the previous summer.