7 March 2005The Manila TimesBy Ronnie E. Calumpita
Global warming is causing the unusually cold nights that have gripped Metro Manila during the past days, the weather bureau said Sunday.
The temperature dipped to the low 20s in degrees Centigrade over the weekend, at a time when nights begin to get uncomfortably warm as summer sets in.
At 6 a.m. Saturday, the temperature monitored at the Science Garden in Diliman, Quezon City, registered 22 degrees Centigrade. In summer the temperature could reach as high as 37 degrees Centigrade.
On Friday and Saturday evening, light rain also fell in parts of Luzon, including Metro Manila. Cool, strong breezes also blew across the metropolis.
Francis Aranador, a weather forecaster at the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa), attributed the unusual weather to the still active northeast monsoon, which brings cold air from mainland China from October to February.
"Since there is an abnormality in our weather owing to global warming, the northeast monsoon is still affecting the country," Aranador said in a telephone interview.
Global warming is the gradual increase of the temperature of the Earth's lower atmosphere as a result of a buildup in greenhouse gases composed largely of water vapor, carbon dioxide, methane, nitrous oxide and ozone.
\t "_top" Infrared radiation reflects off the earth's surface toward space but does not easily pass through the thermal blanket. Some of it is trapped and reflected downward.
The tail end of the cold front and the northeast monsoon contributed in the cold spell, Aranador explained. A cold front develops when cold and warm air masses collide.
Pagasa expects the northeast monsoon to stop blowing by the third week of March, paving the way for the start of summer at end of April or middle of May.
The southwest monsoon, or hanging habagat, which comes from the southwest and brings monsoon rains, usually starts to affect June until September.
