Featured image: Destroyed wheat crops in Bihar after unseasonal rains. Photo: Saurav Kumar
Patna: Rapid changes in Earth’s surface temperature are affecting weather and climate patterns across the globe – and Bihar is witnessing similar developments.
The changes in surface temperature over Bihar are going to create new challenges – of uncertain intensity – for cropping patterns, according to a study by experts at the Central University of South Bihar, Gaya (CUSB). Such changes have crucial implications for agriculture and water availability.
Pradhan Parth Sarthi and Praveen Kumar at CUSB found that variations in surface temperature have an adverse impact on cropping patterns. Their paper was published in May 2019, in which they suggested that the period 2021-2055 will witness changes in Bihar’s land surface temperature.
Also read: Unseasonal Rains, Hail Damage Rabi Crops Across North India
Sarthi told The Wire Science that in Bihar, an increase of 0.3-0.5º C is possible between 2021 and 2055. This will likely be the average increase in surface temperature; individual years may see fluctuations in either direction.
Between March and May, the maximum temperature may increase by 0.68º C in this period, while between December and February, the maximum temperature could go up by up to 1.7º C. According to the study, then, maximum temperatures are likely to increase more in winter than in summer.
Sarthi said this possible increase in surface temperature is very alarming, and may especially affect the agricultural sector in the state. Such warming trends in the March-May period may increase the number of heat waves, while warming in December-February may impact winter crop – particularly wheat – production.
The two scholars used 43 climate models designed by the Intergovernmental Panel on Climate Change (IPCC) for their study. Sarthi is the president of the Indian Meteorological Society, Bihar, and a steering committee member of the Bihar State Action Plan on Climate Change.
Buxar-based agricultural scientist and former director of the Patna Agriculture Institute Ajay Kumar said that the relationship between the climate and agriculture is direct, and is becoming more unpredictable. This is why, he explained, we’re seeing altered cropping patterns. Since Bihar’s economy is largely agrarian, this could lead to a range of negative effects.
Kumar added that the study suggests an effect on temperature and rainfall. That is, there may be more intense rainfall and longer dry spells in the kharif (monsoon) cropping season. Staple crops could bear the brunt of this, and serious policy interventions could be needed to mitigate the impact.
Also read: Rainfall Declining in Seven States, Analysis of 30 Years of Data Shows
In the ongoing rabi season, crops have been destroyed in several of Bihar’s districts due to heavy rainfall and hailstorms. The destruction occurred in phases: until the last week of February, crop was lost over 31,929 hectares in 11 districts, according to state agriculture minister Prem Kumar. And according to the India Meteorological Department (IMD), Gaya received the most rain – 43 mm – followed by Rohtas, Sabour, Patna and Muzaffarpur.
Since April 15, five days of stormy weather with unseasonal rain and heavy hailstorm extensively damaged wheat, maize, mango and banana crops in the northern districts of Kosi and Seemanchal. The damage could result in lower procurement of food grains than expected.
The NSSO report for 2018-2019 clearly stated that the impact of climate change has been reflected in farmers’ incomes in Bihar, and contributes to the state’s persistent poverty. Low yields were noticeable in both the previous kharif and rabi seasons. For example, the yield of kharif maize dipped 19.07%.
The IMD’s state chapter is expecting temperatures to rise between March and May, with a 43% probability that they will remain 1º C above the corresponding normal in the core heatwave region over Bihar.
Uncertain climate patterns have been visible for the last few years over Bihar. Last year, 22 districts in the south experienced a drought-like situation even as 12 in the north reeled under a flood.
In 2018, the state government declared 275 blocks, of 534, to be drought-affected. On the other hand, due to heavy rain and floods, the agricultural department recorded no kharif crops (largely paddy) being sown on a million hectares across the state.
A telemetry report released in January indicated a dip in groundwater levels in at least 10 districts: it was reported to be between 60 ft and 250 ft, while it used to be between 40 ft and 200 ft. The Bihar State Disaster Management Authority has especially been concerned about a dip in north Bihar districts – traditionally known for good rainfall – during the winter season, prior to a hot summer.
A recent study by the Central Ground Water Board suggests that at least eight cities – including the capital, Patna – and 11 blocks of different districts in Bihar are likely to face a severe water crisis soon.
The study by CUSB scholars on changes to surface temperature and the impact they may have is related to what we’re seeing in the state now – unseasonal hailstorms, heavy rain, falling groundwater and greater farmers’ distress.
Saurav Kumar is an independent journalist.