The adverse impacts of climate change have started manifesting themselves in various forms, far more visibly in the agricultural sector.
The country's farmers are now in doldrums as the prevailing drought conditions are causing significant damage to standing crops, while extra irrigation expenditure due a lack of normal rainfall is pushing the production cost up.
Boro paddy cultivation has exceeded this year's target by about 83,000 hectares of land aiming to tackle the looming food crisis amid the ongoing coronavirus pandemic.
But, standing paddy on over 55,000 hectares of land has been affected by the recent nor'wester and heat shock, according to the Department of Agriculture Extension.
Of this, paddy on 14,000-15,000 hectares of land has been completely damaged due to the heat shock.
This huge amount of paddy would not have been damaged, had it rained during the heatwave or in a certain period after that, said Md Asadullah, director-general of the Department of Agricultural Extension.
Paddy fields that were at the flowering stage or milking stage were damaged by the heat shock. Had rained with the wind, this damage would not have happened
Asked about this, Nazmul Bari, chief scientific officer of Rice Research Institute in Gazipur, told The Business Standard, "Paddy fields which were at the flowering stage or milking stage were damaged by the heat shock. Had rained with the wind, this damage would not have happened."
He said the normal temperature at the flowering stage should be 25-30 degrees Celsius, but at the end of March this year the temperature in different regions was constantly between 34 and 35 degrees or even higher.
"Excessive temperature prevents pollination of paddy. But if it had rained normally at this time of the year, the temperature would have dropped significantly."
Agriculture department officials said normal rainfall in March-April could help reduce the cost of Boro cultivation. If the temperature remains high for a long period, the production might be less.
Although the effect is not obvious in the plains due to the irrigation process, the char areas are the worst affected.
Not only paddy, a lack of rainfall leads to reduced yield of fruits as well, said the officials.
On the other hand, the production of Aus is entirely dependent on rainfall. If there is no normal rain at that time, the yield in 10-12 lakh hectares of Aus land is hampered fully. In case of heavy rainfall and flooding, a crisis is created also during the Aman season besides the Aus season.
Scientific officer Namjul Bari said the effects of climate change are constantly challenging agricultural production. There is a need for more research on the harms caused by a lack of normal rainfall, he added.
According to a forecast of the Meteorological Department, there was no normal rainfall in all parts of the country except Sylhet and Rangpur divisions last March.
Rainfall figures for the whole of Bangladesh show that the rainfall was about 80% less than normal. Of these, only Sylhet division saw normal rainfall.
It is learned that Dhaka witnessed 92.5% less rainfall than normal in March this year. For Mymensingh it was 23% less, Chattogram 99.6%, Sylhet 1%, Rajshahi 94.2%, Rangpur 46.5%, Khulna 94.7% and for Barishal the rainfall was 99.5% less than the normal level.
The situation was almost the same in March last year, but there was good rainfall in April. However, March-April 2019 saw the highest rainfall in three years.
Under normal circumstances, 10-25% of annual rainfall occurs between March and May every year. Concerned quarters said due to the adverse effects of climate change, normal rainfall did not occur in March this year.
About 70-80% of the yearly rainfall occurs during the monsoon season (June to October). Rainfall in this period was reported to be slightly higher than normal in 2019 and 2020.
However, according to the forecast of the Department of Environment, there is a possibility of normal or slightly more rainfall in every part of the country this April. There is also a possibility of a cyclone.
Agriculture department officials said the impact of low rainfall has increased the cost of irrigation for Boro farming by 1.5-2 times in the char areas.
Not only Boro, but also wheat, maize and vegetable plantations have to be irrigated a lot. Whereas, normal rainfall reduces the cost of irrigation i.e. production cost.
"The impact of drought does not have much of an impact on the irrigation-dependent Boro season. However, the effect of drought on fruits is immense. Buds and immature fruits drop and fruit size becomes smaller if there is scanty rainfall. If there is no rain during the time when the biggest supply of summer fruits comes, the overall production takes a big hit."
Lalbanu, a farmer from Ghorjan union in Sirajganj's Chowhali upazila, told TBS, 'The higher the rainfall, the lower the cost of irrigation. If it doesn't rain, you have to irrigate more and the cost of production goes up."
Abdul Hamid Mia, deputy director of the Sirajganj Department of Agricultural Extension, told TBS, "Boro is not widely cultivated on char lands. Mostly, wheat, maize, mustard, vegetables, fruits and pulses are grown there. Normal rainfall helps to keep the production cost of these crops normal."
Agriculture officials said drought leaves a major impact on fruit production. About 60-70% of summer fruits are produced at this time of the year.
If there is no normal rainfall, there is a possibility of bud and fruit drops, they said, adding fruit size becomes smaller due to less rainfall.
Kartik Chandra Chakraborty, director of the Agricultural Information Service, told TBS, "The impact of drought does not have much of an impact on the irrigation-dependent Boro season. However, when it rains, the cost of production naturally goes down."
He, however, said the effect of drought on fruits is immense. "Buds and immature fruits drop and fruit size becomes smaller if there is scanty rainfall. If there is no rain during the time when the biggest supply of summer fruits comes, the overall production takes a big hit."
This time of the year is the big production season of various fruits including mango, jackfruit, litchi and guava.
Officials from the Department of the Environment and the Department of Agriculture Extension said normal rainfall is not happening due to the effects of climate change and its impact is clearly felt in agriculture.
Rainfall occurs naturally during or immediately after a storm. But the heat shock that has damaged paddy in different areas including Barishal, Kishoreganj, Netrokona, Sherpur is a big example of the impact of climate change, they mentioned.