This is typical fall weather. Short days, gray skies, heavy rains. However, the level of the department's rivers has risen sharply in recent months, to the point of wondering whether it is raining more than usual in recent weeks.
« In the month of October, we had 129 mm of water in Tours, or 96% more rain than normal for the season. », shares Olivier Renard, president of Météo Centre. Seasonal normals are the average of these same measurements over the last 30 years.
At the beginning of October, the passage of Storm Kirk placed Indre-et-Loire on orange rain flood alert. In more detail, the heavy rains that occurred in October can be deciphered into three phases. “ There was a first episode on the days of October 7, 8 and 9, which brought 65 mm of water in three days. The two other episodes of rain occurred on October 16-17 and then October 25-26. », analyzes Olivier Renard, consulting Météo Center measurements. “ We have a recurrence of rainy episodes », he adds.
Furthermore, even though 2024 is not over, it is already the second rainiest year of the last two decades, with 755 millimeters of water recorded in Tours. 2012 is the only year when it rained more, when 775.8 millimeters of rainwater fell in Tours.
Climate change
A recurrence which risks increasing, because these heavy rains are a consequence of climate change.
« The warmer it is, the easier it is for the oceans to evaporate and recharge the atmosphere. The air itself in its physical properties, with the heat, will then contain more water vapor. For every degree the temperature rises, humidity increases by 7% in the atmosphere, leading to more precipitation. », explains Olivier Renard.
A consequence of climate change which can be more difficult to perceive than episodes of extreme heat. “ In recent years, we have had periods of drought, which are a marker of climate change. But on top of that, we are going to have a lot more intense and recurring precipitation, which is also a marker of global warming. », underlines the member of the Superior Council of Meteorology.
If summers are sometimes marked by significant aridity, and sometimes by torrential rains, this is due to the ” movement of anticyclones and depressions, which means that precipitation can be brought towards France or blocked in northern Europe »comments Olivier Renard.
