Droughts are a pressing issue that is affecting the planet on a global scale. While changing rainfall patterns play a significant role in the severity and spread of droughts, there is another factor at play – the increasing thirst of the atmosphere.
A recent study published in Nature has shed light on this phenomenon, known as atmospheric evaporative demand (AED). The research indicates that AED is responsible for approximately 40% of the heightened severity of droughts over the past four decades. In simple terms, AED can be likened to spending, where the atmosphere demands more water than the land can sustainably provide, leading to a deficit in water resources.
As the Earth’s temperature rises, the demand from the atmosphere for water also increases. This results in the extraction of moisture from various sources such as soils, rivers, lakes, and plants. Even in regions where rainfall has remained relatively stable, the intensified AED is causing droughts to become more severe.
The concept of AED quantifies how much water the atmosphere requires from the surface. Factors such as temperature, sunlight exposure, wind speed, and humidity influence this demand. As these conditions become more extreme, the atmosphere becomes “thirstier,” exacerbating the drying out of landscapes and intensifying drought conditions.
Moreover, the study reveals that AED not only exacerbates existing droughts but also expands the areas affected by drought. Between 2018 and 2022, there was a 74% increase in the global land area experiencing drought, with 58% of this expansion attributed to heightened AED.
The year 2022 was particularly notable for its widespread drought conditions, with over 30% of the world’s land facing moderate to extreme drought. Regions like Europe and East Africa experienced severe droughts, driven primarily by the sharp increase in AED, even in the absence of significant rainfall reduction.
The implications of rising AED are profound, especially for regions already prone to drought vulnerability. Without accounting for AED in drought monitoring and planning, governments and communities may underestimate the true risk posed by droughts. With global temperatures projected to rise further, the frequency and severity of droughts are expected to escalate, necessitating proactive measures to mitigate their impact.
Understanding the drivers of drought in specific locations is crucial for effective climate adaptation strategies. A focus on AED as a key factor in drought monitoring and planning can inform tailored approaches to address evaporative loss and plant water stress. This may involve implementing measures such as planting drought-resistant crops, optimizing irrigation systems, improving soil health, and restoring habitats to retain moisture in the land.
In conclusion, the research underscores the importance of acknowledging and addressing the growing atmospheric thirst that is exacerbating drought conditions worldwide. By incorporating AED into drought management strategies, we can better prepare for the challenges posed by increasingly severe and widespread droughts.
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This article is based on a study published in Nature and has been rewritten for a WordPress platform while retaining the key points and original HTML tags from the source article.
