This summer, global temperatures reached unprecedented levels on July 4, making it one of the hottest days ever recorded on Earth, as revealed by climate data from the U.S. National Centers for Environmental Prediction. The average global temperature on that day was approximately 63 degrees Fahrenheit, marking it as one of the warmest in the past 125,000 years.
Anthony Lupo, a renowned professor of atmospheric sciences in the College of Agriculture, Food and Natural Resources at the University of Missouri and the state’s interim climatologist, has extensive expertise in predicting climate patterns. Lupo sheds light on the interplay of extreme weather phenomena that are impacting the Midwest and causing a severe drought.
What are the drought patterns in Missouri over the past couple of years?
In the Midwest, the development of drought is a gradual process that typically spans over several months. This trend has persisted in recent years due to recurring shifts between El Nino and La Nina climate patterns in the Pacific Ocean, which influence global weather conditions. In 2020, the region experienced a La Nina pattern, and this trend has continued since then. Despite the switch to El Nino in 2023, which typically brings more rainfall, the Midwest faced extreme drought conditions in July. This defied expectations, as El Nino summers tend to be favorable for rainfall. However, there is still a slight possibility of a dry summer during El Nino, and unfortunately, that is what we are witnessing this year.
What atmospheric event marked the start of this year’s summer drought?
The onset of drought conditions can be attributed to an atmospheric event that took place in early June 2022. During this event, the jet stream underwent a sudden shift, altering its energy. These shifts occur approximately every eight to 10 days, averaging about 30 times a year. Stable jet stream conditions facilitate accurate weather forecasting, while transitional periods make it more challenging.
How do extreme drought conditions affect agriculture in the Midwest?
The previous year’s drought significantly impacted agricultural production, leading to lower yields. Currently, the crops appear to be in good shape because they have been receiving just enough moisture to sustain them through the summer. However, there is no substantial reservoir of water beneath the surface, and the subsurface remains dry from the previous year. Consequently, there is a risk of reduced agricultural production if prolonged dry spells occur in July or August.
What weather can people expect through the end of the summer?
Expect temperatures to rise as the summer progresses. So far, we have been fortunate to experience temperatures slightly above normal but within the expected range. However, if we encounter a series of 100-degree days with low humidity, this will change.
How does hot, dry weather impact people’s health?
Hot and humid weather tends to keep nighttime temperatures elevated, posing risks to human and animal well-being. In contrast, dry conditions often lead to cooler nights, allowing the body to rest and recover from the heat, thereby preventing heat-related deaths. Additionally, prolonged dry weather causes soil to dry up, potentially affecting infrastructure such as the foundation of buildings and water systems. It also leads to increased tree mortality, impacting the local environment not just this year, but for the following two years as well.
Citation:
Q&A: What’s causing the severe Midwestern drought? (2023, July 19)
retrieved 20 July 2023
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