Drought like conditions, rainfall deficits, heat waves, and increased evaporation have depleted some of central and eastern European groundwater supplies.

High temperatures have caused billion dollars of loss in revenue over the past year, as record temperatures in July 2019 caused the power plants to shut down, leading to delays in train and damaged crops. 2019-2020 winter in Europe was the warmest on record with very little snowfall, while the spring season was also dry and warm than usual, as historic heat wave occurred in mid of May. Summer 2020 forecast is not looking much better, as for the third year in a row Europe is facing potential water woes.

Droughts in Europe

In early spring 2020, meteorological drought like conditions started in eastern Europe and migrated across the continent with drier-than-normal weather in April and May. Tributaries from rivers such as the Elbe, Warta, and Danube, fell below normal seasonal flow.

“In recent times, Central European countries have experienced several droughts resulting from exceptionally stable weather patterns and high temperatures, both of which could be linked to climate change,” said Wolfgang Wagner, a scientist at Technische Universität Wien, Austria. “The fact that some regions have experienced drought conditions in several consecutive years has already caused significant damage to forests (due to bark beetle infestation) and declines in groundwater levels.”

Scientists at the Copernicus Climate Change Service (C3S) conclude that climate models show that hotter and drier weather is likely to hit agricultural regions across the European Union, creating drought like conditions that have been made worse due to climate change. These dry summer conditions is posing troubles for farmers, unities and transportation services on inland waterways.

C3S scientists predict with a 50% probability that temperatures across France, Spain and Italy will be well-above average in July. The climate model used in the study combines data from scientists in the USA, UK, Italy, Germany, and France, as the EU program utilizes billions of satellite, ship, aircraft, and weather station measurements from around the world for its monthly and seasonal forecasts.

C3S researchers hypothesized with a 40% probability that rainfall across swathes of central Europe, France and Spain will be well-below normal. Consistent droughts puts stress on the production of crops like wheat and corn, and is threatening to disrupt food output.

The models developed by C3S scientists will help businesses and governments to plan accordingly in mitigating weather and climate related risks and hazards. According to Copernicus scientists, there is more than 60% probability that large sections of the U.S. along the east and west coasts will have a record well-above-average temperatures in July.

Impact of Droughts on Groundwater supply in Europe

Groundwater is an indispensable resource for crop irrigation and drinking water, and it also sustains streams during dry periods. Unlike other forms of water bodies, groundwater takes months to replenish, as it gradually recharges by surface moisture that seeps below the ground via soil and rock bodies. As majority of Europe has experienced drought in the summers of 2018 and 2019, and little snowfall was observed in the winter season of 2019-20, much of the continent began this year with a significant deficit.

After 6 years of rainfall shortages, the Czech Republic reported this spring that almost 80% of its wells recorded mild to extreme drought. Soil moisture in the month of May for Czech Republic was found to be at least 30% less than normal. Some climatologists have called it the country’s worst drought in 500 years. Meanwhile, in neighboring country – Germany, the groundwater has also been depleted in recent years.

Climatologists from Poland also reported one of the worst droughts in a century, as agricultural drought hit 11 of 16 provinces. While more than 40 polish streams and rivers fell critically below normal levels by May 2020. Vistula river, the largest water body in Poland also experienced its lowest level on record in 2019. These low water level posed trouble for the electric power industry, which sometimes cannot draw enough water for cooling.

In Ukraine, the water level in the Desna River reached it lowest point in 140 years of observations – a full 5 meters below normal for springtime. Dnieper watershed, which is the source of half of Ukraine’s water requirements, received just 70% of its usual rainfall from September through May. In early June, reservoirs around Kyiv were at their lowest levels in nearly a century.

“From a global food security and agricultural commodities perspective, European region is significant due to the fact that it is one of the largest wheat-producing regions in the world, and a major maize-producing region. Both wheat and maize are major food security crops,” said Brian Barker, a leader of the GEOGLAM group and scientist at the University of Maryland. “The dourght like conditions, with rainfall shortagse and warmer temperature since winter, have negatively impacted large areas across Europe, reducing forecasted crop yields compared to the five-year average in a number of countries.”

Image Credit: NASA Earth Observatory
Map showing groundwater (storage) wetness in Europe

European drought

Image Credit: NASA Earth Observatory
Map showing root zone (moisture) wetness in Europe

The map demonstrates shallow groundwater storage and root zone soil moisture in Europe as of June 22, 2020, measured by the Gravity Recovery and Climate Experiment Follow On (GRACE-FO) satellites. Monitoring root zone moisture is useful for agricultural management as it represents water that is naturally available for crop growth. Soil moisture at Earth’s surface and in the root zone can vary over over short periods of time; can be replenished by rainfall, but also can evaporate rapidly during heat waves and dry spells.

The colors in the map shows wetness percentile (how groundwater levels and soil moisture relate to long-term records for the month). Regions with blue color represent abundance of water than usual, and orange and red areas represent less availability of water. The darkest red colors on the map show dry conditions that should occur only 2 percent of the time (once every 50 years).

GRACE-FO detects water movements based on variations in Earth’s gravity fields. Subtle differences in gravity are measured using GRACE-FO, as change in land topography or ocean tides alter the distribution of Earth’s mass, the addition or subtraction of water also alters the gravity field. This data is correlated with historical data and ground level observations using numerical modeling of water and energy processes on land.

NASA Earth Observatory images by Lauren Dauphin, using GRACE data from the National Drought Mitigation Center


STORY

Signs of Drought in European Groundwater
Michael Carlowicz and Matt Rodell | June 22, 2020 | NASA Earth Observatory

CITE THIS ARTICLE: "European groundwater supply threatened by droughts in 2020," in Geoscience Daily, June 29, 2020, https://geosciencedaily.com/environment/european-groundwater-droughts-2020/.