The combination of the latest El Nino episode, which is a marked increase in Pacific Ocean temperatures, and climate change, have adversely impacted weather and thus agricultural production all over the world over the last few months. In June 2023, NOAA announced that a new El Nino episode is underway, the first one since 2018-2019. To make such a determination, they must find that monthly sea surface temperatures in the central and eastern tropical Pacific Ocean are expected to warm +0.5° Celsius above normal, with the expectation that the warming will persist for at least five consecutive overlapping three month periods. The National Oceanic and Atmospheric Administration (NOAA), is the government agency within the U.S. Commerce Department which is charged with “bettering our understanding of our natural world and helping to protect its precious resources, which extends beyond national borders to monitor global weather and climate.”
The effects of El Niño are typically focused in the southern hemisphere, leading to reduced precipitation and increased chances for droughts and wildfire in places such as Indonesia and Australia. However, with the current El Niño only having been identified in the last few months, it may be too early to specifically attribute any recent weather events to this periodic phenomenon.
With respect to the concentration of greenhouse gas emissions that have generated climate change over the last several decades, the levels have resumed their rise in the last few years after slowing as a result of the economic lockdowns imposed in most countries during 2020 due to efforts to slow the spread of the COVID-19 pandemic. Globally, GHG emissions are estimated to have dropped 4.6 percent in that year, but increased 6.4 percent in 2021 and 0.9 percent in 2022, which was somewhat less than expected. As of May 2023, the U.S. observatory at Mauna Loa in Hawaii recorded a new record high carbon dioxide (CO2) concentration level of 424 ppm, a 7 percent increase since 2010 (figure below).
Source: Climate.gov
Scientists are increasingly attributing the serious weather events that have occurred so far this year to climate change, at least insofar as climate change has extended or amplified certain extreme weather events. These include the recent heat domes that battered the U.S. Southwest earlier this summer–temperatures exceeded 110 degrees F for 31 straight days in Phoenix, AZ–or the extensive wildfires in central Canada that have scorched more than 37 million acres through mid-August. A shift in prevailing winds brought smoke from those wildfires to the U.S. east coast in June, bringing air quality to dangerously hazardous levels in cities like New York and Washington DC.
We do know that the planet experienced its hottest global average temperature on record in early July of this year, with the record being broken on four consecutive days between the 3rd and the 6th according to data collected by the European Union’s Copernicus Climate Service since 1940. The new record is 17.23 degrees Centigrade (63.1 degrees Fahrenheit). This figure averages temperatures in the northern hemisphere, where it was the height of summer, and the southern hemisphere, where it was the middle of winter. Australia just closed the books on what was likely its warmest winter in history.
One of the most vivid manifestations of climate change in recent years has been the emergence of persistent and expansive wildfires around the world. In 2023, in addition to the Canadian fires mentioned above, wildfires in Hawaii, Laos and Kazahkstan in Asia, Greece and Italy in Europe, Algeria and South Africa in Africa, and Chile and Argentina in Latin America have consumed millions of acres and killed dozens of people so far.
The bad weather caused by the combination of El Nino and climate change has already had some impact on this year’s crops. The winter wheat crop, planted last fall in several Plains states and harvested this summer, received relatively little winter precipitation and was under severe heat stress in key producing states such as Kansas in the early summer. In June 2023, USDA projected a 22 percent decline in that state’s winter wheat production as compared to last year’s level. While the current projection for overall U.S. production level for hard red winter (HRW) wheat is actually slightly increased over last year, it is feared that the weather problems mentioned above likely created serious quality problems for the crop.
The August 2023 World Agricultural Supply and Demand Estimates (WASDE) publication by USDA projected only a modest decline in corn and soybean yields for the 2023/24 crop, despite the severe or extreme drought afflicting key regions of the main producing states in the Midwest. Their current national estimates of 175 bushels/acre for corn and 50.9 bushels/acre for soybeans represent a slight decline relative to recent trends but are still modestly higher than yields for the 2022/23 crops. However, the recently completed Midwest crop tour conducted by Pro Farmer found the August USDA estimates to be slightly inflated, projecting 172 bu/acre for corn and 49.7 bu/acre for soybeans instead.
A significant portion of the world’s agricultural lands was still suffering from low soil moisture and groundwater levels as of late July. The GEOGLAM Crop Monitor indicated that agriculture was most threatened in parts of the Americas, Africa, and Asia, and in southwest and eastern parts of Europe and southwest Australia. Despite those areas of concern, USDA was predicting in its August WASDE report that world wheat, rice, and coarse grain production for the 2023/24 crops would be higher than for the last two years, but reduced production is expected in major exporting countries for wheat and only slightly increased for coarse grains and rice exporters. Total exports of wheat and rice are expected to decline in 2023/24 compared to the previous year’s level.
