The unseasonably heavy rains that have hit Phnom Penh and other parts of the country indicate that the rainy season has started early this year, Ministry of Water Resources officials said Tuesday. And the early start to the annual deluge has prompted the Ministry of Agriculture to prepare farmers for a possible drought later in the wet season.
Oum Rina, deputy director-general of the water resource department at the Ministry of Water Resources and Meteorology, said rains started to fall in Phnom Penh and in Kandal, Kompong Cham, Svay Rieng, Preah Vihear, Stung Treng and Ratanakkiri provinces over the past week. The fact that rains have started in mid-April—at what should be the height of the hot season, instead of May as is usual—means the rainy season is under way and will finish in September and not around December as in most years, he said.
The early start of the rainy season is highly uncommon and is also exceptional because of the uneven geographical spread and limited amount of rainfall in some areas so far, he said.
“It is different from other years because usually it starts [to rain] everywhere,” he said.
Mr Oum Rina added that the rains so far have been limited to short showers in the evening and at night, as opposed to the longer periods of rain that are common at the start of the wet season. This, he said, could indicate there might be a lack of rain overall this year.
The unusual weather might be due to the effects of global climate change, he added.
Seth Vannareth, director of the ministry’s meteorology department, was not in Cambodia on Tuesday and could not be reached for comment.
Agriculture Minister Chan Sarun said he had been informed by the Ministry of Water Resources that rains would be good in the early part of the rainy season, which has now started, but that there could now be an extended dry spell in the middle of the season.
A short dry period of a few weeks in the month of July is common in Cambodia, but this year, Mr Chan Sarun said, this period might last as long as six weeks.
The unpredictable weather could affect farmers, and agriculture officials at the provincial level have been instructed to advise rural dwellers to use rice varieties with a relatively short growing period, he said.
“This year there would be good rains in the beginning of the season. There would be drought in July. It could affect the transplanting [of rice seedlings],” the minister said. “I think farmers should not plant the rice seed with a long growing period. All the farmers should be careful,” he added.
Cambodian farmers commonly use rice varieties that vary in growing periods from just a few months to up to six months depending on climatic conditions.
According to Mr Chan Sarun, the early rains were due to the phenomena of “El Nino” and “La Nina,” in which surface water temperatures in the Eastern Pacific Ocean cause weather and climates around the world to vary every three to eight years.
Tin Ponlok, national coordinator for the government’s climate change office, said it was scientifically impossible to blame the early rains on climate change.
“We cannot draw any conclusion from these events…. This type of anomaly may be a fluctuation,” Mr Tin Ponlok said.
“It is possible, but how likely is that?” he said, adding: “Even the UN’s Intergovernmental Panel on Climate Change never talks about how likely it is that climate change is [already] affecting the weather.”
Mr Tin Ponlok said his climate change office is analyzing Cambodian rainfall and temperature data stretching back 40 years for a national report that is due at the end of this year. The report, which would be sent to the UN Framework Convention on Climate Change, will contain climate change projections along with strategies to cope with possible impacts, he said. (Additional reporting by Chhorn Chansy)