Climate change at the Ebro Delta

From the data from the Ebro Meteorological Observatory in Roquetes, and from those collected in the BAIC 2019 (Annual Bulletin of climatic indicators edited by the Meteorological Service of Catalonia), we show the difference (anomaly) of the temperature and precipitation values from 1950 2019 (70 years of data) compared to the period 1981 to 2010. Thus, an anomaly of +1 ° C informs us that the temperature has deviated 1 ° C above the average.

Temperature

The year 2019 was the 5th hottest year in Catalonia since 1950, with an anomaly of +0.91 °C.
Specifically, 2019 was the hottest year since 1905 at the Ebro Observatory (Baix Ebre) and the 3rd hottest since 1914 at the Fabra Observatory (Barcelonès).
Currently, the temperature in Catalonia is 1.7 °C degrees higher than the average for the 20th century, increasing at a rate of +0.25 °C/decade.
Daytime temperature is increasing at a higher rate than night temperature: +0.32 vs. +0.19 °C/decade (1950-2019).
Summer is still the season with the highest temperature increase, +0.37 °C/decade, which means that currently, the summer temperature is 2.6 °C higher than the average for the 20th century.

Average yearly temperature anomaly. Ebro Observatory (1905-2019)

Annual precipitation anomaly. Ebro Observatory (1905-2019)

Precipitation

On average, the annual precipitation in Catalonia has currently decreased by 65 mm with respect to the average for the 20th century (rate of decrease of -1.6 %/decade).
Summer precipitation is the only one that shows a clear and strong trend in the whole country, decreasing an average of 6% each decade in the past 70 years.
The year 2019 was very dry at the Ebro Observatory, registering 329.1 mm of precipitation (variation of -36%). It was the 11th driest year on records since the series began, in 1905.

In an area like the Ebro Delta there are two other parameters to analyse from the perspective of climate change: the temperature of the sea water and the rise in sea level.

Sea Temperature

The average yearly sea temperature has increased significantly at every depth level since 1974.
At the surface it has increased by +0.32 °C/decade, at 20 m depth it increased by +0.30 °C/decade, at 50 m depth at a rate of +0.26 °C/decade and at 80 m by +0.20 °C/decade.
By season, autumn and summer are the times of the year that have a higher tendency of warming, especially at 20 m and 50 m depths, with values that are greater than +0.30 °C/decade.

Rise in Sea Level

Sea level shows a statistically-significant rising trend of +3.3 cm/decade for 1990-2018.
The global effect (on the entire planet) of rising sea level has been +2.0 mm/year from 1971-2010, and increasing to 3.2 mm/year between 1993 and 2010. These figures suggest that the rise in sea level is accelerating due to the melting of the ice poles and the rise in sea temperature.

The effects of Gloria storm

Storm Gloria, which took place between January 19-23, 2020, was a wake-up call as to how fragile the Ebro Delta is

The heavy sea storm broke the sand bar at the Illa de Buda, which caused sea water to enter into the lagoon and had a direct impact on the fish population. More than 2,300 hectares of rice fields were flooded, numerous infrastructure elements were damaged and the Trabucador sand bar vanished, submerged into the sea. According to climate change projects, weather events like Storm Gloria could become increasingly more frequent.

Effects of Gloria storm