The Azores high-pressure system has undergone significant changes in the last century due to climate change. As a result, Spain and Portugal have experienced a significant decrease in rainfall, putting their wine and olive production at risk. The Azores high-pressure system has a significant impact on weather and long-term climate development in Western Europe. During the summer months, the high-pressure system sends hot and dry air to France, Spain, and Portugal. In the winter, it causes moisture and precipitation, which are essential for the ecological and economic survival of the Iberian Peninsula. However, parts of Spain and Portugal are currently so dry that the water supply is insufficient for many plants. Despite artificial irrigation, wine and olive production are at risk.
A team from the Woods Hole Oceanographic Institution (WHOI) led by Caroline C. Ummenhofer has investigated whether the extreme drought is caused by short-term weather changes or long-term changes in the Azores high-pressure system. According to their publication in the journal Nature Geoscience, they analyzed the changes in the Azores high-pressure system over the last 1,200 years using a climate model. They determined that the high-pressure system has undergone “dramatic changes” in the last century and that “these changes in the North Atlantic climate are unprecedented within the last millennium.” The expansion of the high-pressure system began about 200 years ago when greenhouse gas concentrations in the atmosphere increased. In the 20th century, further expansion occurred due to climate change and global warming. This caused a decrease in winter rainfall in the western Mediterranean region.
In the 21st century, the Azores high-pressure system will expand over even larger areas due to ongoing climate change. By 2100, rainfall in already dry regions will decrease by another ten to twenty percent, threatening local agriculture. According to the study, wine production in the Iberian Peninsula could decline by a quarter by 2050, and olive production in southern Spain could decrease by 30 percent by 2100. The findings of this study highlight the urgent need for action to mitigate the effects of climate change and protect the livelihoods of those who depend on agriculture in the affected regions.
