Human-caused climate change is driving drought conditions across the Northern Hemisphere, with soil moisture deficits intensifying drought impacts and stressing food systems. A recent assessment by the World Weather Attribution (WWA) group, confirmed by the Spanish meteorological agency AEMET, links this year to record warmth on the Iberian Peninsula and marks it as the warmest period in recent Iberian history.
The same analysis indicates that human-induced warming makes soil moisture droughts at least twenty times more likely to occur and to be more severe, contributing to lower crop yields, higher food prices, and increased food insecurity.
The Northern Hemisphere summer of 2022 ranked among the hottest on record in Europe, coinciding with thousands of heat-related deaths and intense heatwaves that stretched across parts of China and North America. The heat and dryness led to crop shortages, reduced water availability, and pressure on electricity supplies in many regions.
To quantify the influence of human activity on soil moisture, researchers analyzed meteorological observations and computer simulations, comparing current conditions—shaped by about 1.2°C of warming since the late 19th century—with historical climates. The study follows peer-reviewed methods to estimate drought risks in today’s climate.
The scope of the study covered June to August 2022 across the Northern Hemisphere, excluding tropical regions, with a focus on Western and Central Europe where drought damage to crops and water resources was especially pronounced, stretching from the Atlantic coast to the Eastern Black Sea, and from the Mediterranean to the Baltic.
The researchers examined soil moisture in the top 7 centimeters and the top 100 centimeters, the root zone where much of the water is accessed by crops. Drought in this zone is often described as agricultural and ecological drought.
Findings show that climate change increases the likelihood of soil moisture droughts in the extratropical Northern Hemisphere, affecting both surface soil and the root zone. Surface drought is estimated to be at least five times more likely, while agricultural and drought conditions could be at least twenty times more likely under current warming.
In Western and Central Europe, anthropogenic warming has raised surface drought risk by roughly five to six times and agricultural-ecological drought by about three to four times.
Equal drought every 20 years instead of every 400 years
Projections indicate that, under today’s warmed climate, a drought of this scale could recur roughly once every twenty years in the affected regions. If the planet were not warmed by human emissions, historical droughts in the Northern Hemisphere might occur about once every four hundred years, while European agricultural and ecological droughts might fall to roughly sixty to eighty years apart.
Measuring the exact contribution of climate change to agriculture and drought ecology remains challenging. Temperature and precipitation can be tracked directly, but soil moisture requires estimation from models, adding uncertainty to the analysis.
This complexity yields a wide range in results, and the study presents conservative estimates of climate change impacts, acknowledging that actual effects may be higher. While precipitation changes were modest, rising temperatures emerged as the dominant driver of higher drought risk for agriculture and ecology, according to the researchers.
The warming of temperatures across the Northern Hemisphere has made summers like this one increasingly plausible, and scientists note that such heat levels would be unlikely without human-driven climate changes.
The study was conducted by twenty-one researchers from multiple institutions across Switzerland, France, the Netherlands, New Zealand, the United Kingdom, and the United States, under the World Weather Attribution collaboration.
The hottest year in Spanish history
In Spain, the period from January to September 2022 marked the warmest in the historical record, with the country experiencing its third dry spell in modern history according to climate assessments released by the State Meteorological Agency (AEMET).
September overall brought higher-than-average temperatures across mainland Spain, with the average for September surpassing the 1981-2010 reference period by about 0.6°C. It was among the warmest Septembers of the 21st century since consistent records began in 1961.
The southeastern coast of the peninsula, along with much of the Mediterranean, registered extreme warmth, while central and northwestern areas showed varying conditions. The Balearic Islands experienced very warm to extremely warm conditions, and the Canary Islands displayed regional variability.
Temperature anomalies reached close to +2°C in large portions of Catalonia, eastern Aragon, the Valencian Community, Murcia, and eastern Andalusia, with some points near +3°C. The Balearic Islands also showed notable warming, while the Canary Islands varied by region.
The climate balance for the period highlights that the most pronounced warmth occurred from late summer through early autumn, underscoring regional differences across Spain.
The study emphasizes that the precise climate contributions involve a mix of natural variability and human influences, making ongoing monitoring essential for policy and adaptation planning.
Endnotes reflect ongoing observation and assessment by climate scientists and meteorological services across Europe, with continued data sharing and analysis to understand drought dynamics in a warming world.