This is not the best time for agriculturists, especially crop farmers, in some parts of the Iberian Peninsula. New research shows that these areas are at their driest in about 1,200 years, threatening the production of vine and olives.
In the study published in Nature Geoscience, American researchers reported that the expansion of the Azores High is posing a threat. They said changes seen in this high-pressure system in the last century, as a result of the change in climatic conditions, are “unprecedented.”
These changes can have serious implications on the western Mediterranean climate and crop production.
Expansion of the Azores High
The Azores High is a high-pressure system off the Atlantic coast. This area, which researchers say turns clockwise over portions of the North Atlantic, has a major impact on western Europe’s weather and climate trends.
Scientists say the high-pressure system serves as a rainfall “gatekeeper” in Europe. It swells during the winter months and sends rain inland with wet westerly winds. In the summer months, dry air moves down to cause hot conditions.
The rain that falls in winter is critical for food production and the economy of the Iberian Peninsula and the western Mediterranean. It has, however, been reducing and the drop was particularly drastic in the later part of the 20th Century.
The team in this new study used climate model simulations of the past 1,200 years to come up with their findings. They also examined proof of rainfall levels that were stored in Portuguese stalagmites for hundreds of years.
What the researchers found was that there has been an expansion of the Azores High. They stated that this was especially great in the 20th Century due to global warming.
The high-pressure system began to expand over a larger area about 200 years ago, according to the study authors. This was around the time that greenhouse gas emissions started to surge. Findings show that an increase in the greenhouse gas concentrations in the atmosphere during the Industrial Era led to an expansion of the Azores High.
Study authors also noted that western Mediterranean winters have become drier as a result.
Unpleasant effects on agriculture
Researchers caution that the expansion of the high-pressure system is set to continue during the 21st Century as a result of rising greenhouse gas levels. This could make droughts more common on the Iberian Peninsula, harming important crops.
The research team cited predictions that rainfall levels could drop by another 10-20 percent by the close of the century.
“Our findings have important implications for projected changes in western Mediterranean hydroclimate throughout the twenty-first century,” said the researchers.
Agriculture on the Iberian Peninsula would rank among the “most vulnerable in Europe” as a result of the projected further decline in precipitation.
According to research cited in this study, the size of the area fitting for growing grapes on the Iberian Peninsula could reduce by a quarter or more. This area may disappear almost totally by 2050.
Global warming and falling precipitation levels are forcing winemakers around the region to be more innovative. Measures being taken involve shifting vineyards to higher altitudes and cultivating varieties that are more heat-tolerant.
Spain is a leading producer of olives in the world. But scientists forecast a 30 percent drop in olive production in the country’s southern region by the end of this century.