Rising temperatures, erratic rainfall reducing agricultural yield, quality: Meteorologist

By Gunseli Kenarli

ISTANBUL (AA) – Rising temperatures and dwindling rainfall that decrease soil moisture and groundwater levels are exacerbating plant stress and pushing the demand for water in agriculture, according to a Turkish meteorologist.

The fourth part of Anadolu’s series on the effects of El Nino focuses on the effects of the increasing temperatures and erratic rainfall on agriculture.

The UN’s Food and Agriculture Organization (FAO) describes El Nino as a weather phenomenon that poses a high risk to food security. It lists farmers, livestock keepers, and fishermen among the most threatened by El Nino-related risks.

According to an FAO study based on past El Nino events, the weather phenomenon causes below-normal rainfall in June-September, the peak of the monsoon season in much of South Asia, while causing drought in some Pacific islands, bringing the danger of food and water shortages.

On the other hand, it brings above-average rainfall to Central Asia and the Horn of Africa, triggering floods and landslides, and damaging agricultural production.

African countries such as Ethiopia, Sudan, South Sudan, Uganda, and Kenya experience below-average rainfall between July and September in the years when the weather phenomenon is effective, while precipitation decreases between November and March in most of Southern Africa.

This is affecting the yields of some agricultural products and causing problems in the food supply.

In West Africa and the Sahel region, El Nino also causes below-average rainfall between July and September, which coincides with the main agricultural season.

According to FAO, under these conditions, Sahel countries may become more dependent on imports as their crops decline.

Meanwhile in Central America, one of the regions most affected by El Nino, the June-December period is dry and this period is the agricultural season for many crops, especially corn, leaving the countries in the region in an economically challenging situation.

With the combination of climate change and El Nino effects, 2023 was the hottest year in history. In Türkiye, it affected the yields of some crops, especially those that require irrigation, decreased.

According to the Turkish Statistical Institute (TUIK), Türkiye’s paddy production decreased by 5.3%, sunflower by 13.8%, and cotton production by 23.6% in 2023, compared to the previous year.

- Decrease in yield, product quality

Meral Mungan Arda, the UNDP's Türkiye climate change and environment portfolio manager, told Anadolu that in semi-arid regions like Türkiye, El Nino significantly impacts agricultural production. The phenomenon exacerbates drought and heat waves, posing serious threats to both plant and animal production.

She noted that drought and heat waves can alter plant growth periods, increase water demand, reduce yield and quality, and shift harvest times. "These conditions complicate the supply of production materials like seeds, seedlings, and saplings. They also lead to higher product losses, increased plant diseases and pests, and greater pesticide use," said Arda.

She added that heavy rains can lead to floods and soil erosion in agricultural lands, strong winds can damage crops and cause product losses, and rising atmospheric temperatures can trigger insect infestations and agricultural diseases, all of which negatively impact the agricultural sector.

Referring to the slightly cooler phase after El Nino, she said: “As TUIK data shows, there is a decrease in the yields of some agricultural products.”

“El Nino has an important effect on crops like rice and cotton, which require irrigation. Their yield is highly affected by this situation as they will need more water when exposed to heat waves,” Arda added.

“In addition, crops with low water consumption and fast growth, some legumes and oilseeds, are less affected by heat waves,” she said.

“A study on some cereal crops like cotton and sunflower, which are produced and traded in Türkiye, has predicted a decrease in production due to climate change,” added Arda, an environmental engineer by profession.

She said additional studies are needed to better understand the relationship between agriculture and climate so that the impact of climate change on agriculture can be understood more clearly. “An open-to-access database on this issue should be monitored year by year,” Arda said.

Informing farmers about the impact of climate change and extreme weather events on agriculture, and what can be done about it are among some of the precautionary measures, she suggested. “It is important to address the issue with the dimensions of policy, agricultural sector, and financial resources to develop holistic solutions,” the UNDP official noted.

- Rising water needs

Levent Saylan, a faculty at Istanbul Technical University’s (ITU) Department of Meteorological Engineering, said that due to climate change, precipitation is expected to decrease and temperatures are expected to rise which may lead to decreasing water resources and increasing agricultural drought.

He warned that decreasing precipitation and rising temperatures will harm agricultural productivity, emphasizing: "The timing and amount of rainfall are crucial for the yield of crops like wheat, which typically depends on precipitation in our country."

“Climate change may affect this timing and amount,” he added.

He stressed that studies in the Thrace region predict decreased yields for key crops such as wheat and sunflower. Saylan also emphasized that the Aegean and Mediterranean regions could be more severely affected by rising temperatures and reduced precipitation due to climate change.

He emphasized the importance of soil moisture, saying, "The reduction in precipitation across the country decreases soil moisture, which in turn lowers underground water levels and depletes water resources."

“This situation causes more water consumption in agricultural areas and the rise in temperatures stresses plants and increases their need for water,” Saylan warned.

He said that as a result, plants are expected to require increased water in the future.

Saylan added that agricultural diseases and pests also fluctuate according to weather conditions, and therefore agricultural planning should be done by considering these changes.

He also pointed out the importance of continuously monitoring the changes in the agricultural sector and revising farming methods. “Technology should be used for more efficient irrigation methods in agriculture.”

“The possible effects of climate change on the industry should be analyzed from an agricultural meteorological perspective,” he added.

*Writing by Merve Berker