Anticipated Prolonged Droughts Arising from Effects of Climate Change

Anticipated Prolonged Droughts Arising from Effects of Climate Change

Anticipated Prolonged Droughts Arising from Effects of Climate Change


### Droughts in Upcoming Decades May Be More Severe Than Anticipated, Research Indicates

A recent analysis published in *Nature* on Wednesday warns that future droughts may extend longer and be more intense than what current climate models predict. The international group of researchers responsible for this study identified possible biases in the models utilized to forecast drought occurrences under moderate and high emissions scenarios from the Intergovernmental Panel on Climate Change (IPCC). By adjusting these models with real-world data on dry spells between 1998 and 2018, the scientists discovered that drought durations could exceed previous estimates by nearly 10 days.

### Significant Insights: Lengthening Droughts in Key Areas

The research underscores several areas where drought conditions are likely to deteriorate considerably by the century’s end. These regions include North America, Southern Africa, and Madagascar, where the refined models indicate that the longest annual dry periods may approach double the lengths previously anticipated. The results are particularly troubling for the southwestern United States and northern Mexico, where drought conditions could extend by five days sooner than expected by 2040—60 years ahead of earlier forecasts.

Lead author Irina Petrova, a researcher focused on hydrological extremes at Ghent University in Belgium, highlighted the importance of these results for decision-makers. “Our research identifies global regions where existing climate model forecasts of drought escalation are potentially underestimated,” Petrova stated. She called for governing bodies to reconsider future drought threats and to take necessary measures.

### A Global Challenge with Local Distinctions

Although most regions are predicted to face longer and more intense droughts, some areas might experience the contrary effect. For instance, in central East Asia, the intervals of dryness between rainfall events are diminishing at a rate four times faster than indicated by unadjusted models. This trend could elevate flood risks in that region; however, the complexities of climate dynamics in East Asia pose challenges for fully calibrating models for that locale.

Regardless of these regional differences, the overall pattern is unmistakable: most of the world’s landmass will likely encounter a rise in dry extremes in the future. This is particularly alarming, given that a substantial part of the global population already faces water stress, creating a pressing need for immediate action.

### More Severe Than Anticipated: An Ongoing Trend

The conclusions of this research align with a wider trend in recent studies indicating that various climate effects are accelerating beyond expectations. For instance, there is growing evidence that the Atlantic Meridional Overturning Current (AMOC)—an essential ocean current crucial for regulating the climate in northwestern and western Europe—may weaken considerably by 2100. Such a change could trigger dramatic climate shifts worldwide.

Moreover, the swift increase in global temperatures over the last 18 months has raised alarms about the possibility that the rate of warming could exceed IPCC projections. Some researchers, including former NASA scientist James Hansen, have cautioned that escalating warmth might drive the planet’s average temperature above the Paris Agreement goal of maintaining warming well below 2 degrees Celsius by 2050.

### The Necessity for Reevaluation

The latest study emphasizes the significance of rectifying biases in climate models to enhance the precision of drought predictions. “Systematic biases are known to contribute to discrepancies in model forecasts of dry extremes,” the researchers noted. By incorporating comprehensive observations of dry spells from 1998 to 2018, the study aims to bridge these gaps and offer more dependable predictions.

Michael Mann, director of the Center for Science, Sustainability & the Media at the University of Pennsylvania, pointed out that numerous climate models do not consider some processes inherent in extreme weather phenomena like floods, heatwaves, and droughts. “We contend that the models underestimate the effects that climate change is currently having on these extreme events,” Mann said, adding that models adjusted to reflect real-world patterns tend to project more severe extremes.

### Concurrent Wet and Dry Extremes

One of the complexities of climate change is its capacity to cause both intensified rainfall and heightened droughts. As Mann explained, “When it does rain, there’s an increase in the volume of rainfall per event, partially due to a warmer atmosphere retaining more moisture. However, rainfall events are becoming less frequent, and elevated soil temperatures lead to greater moisture loss through evaporation,” resulting in prolonged droughts between rainfall.

This occurrence of concurrent wet and dry extremes has become increasingly apparent in recent years. For instance, in Europe, multiple forest fires ignited in Portugal following a summer of heatwaves and droughts, concurrently, parts of Poland, Czechia, Romania, and Austria suffered devastating floods after an extreme rainstorm.

Joyce Kimutai, a researcher at the Grantham Institute at Imperial College London, stressed that these kinds of extreme weather incidents are precisely what scientists anticipate with climate change. “A warmer atmosphere energized by fossil fuel emissions can retain more moisture, leading to