Because, precipitation (rain+snow) is the source of water for surface water (e.g. streams, lakes, wetlands), crops, as well as groundwater bodies (i.e. aquifers).

Because rainfall patterns directly influence agriculture, water availability, infrastructure resilience, public health, and economic stability. Shifts in precipitation can lead to droughts or floods, threatening food production and water resources, with European farmers already facing billions in annual losses due to extreme weather. These changes also stress urban infrastructure, as seen in the deadly 2024 floods in Spain, highlighting the need for climate-resilient planning. Moreover, increased flooding raises health risks, including waterborne diseases and mental health challenges, necessitating preparedness in healthcare systems. Economically, altered rainfall patterns disrupt key sectors like transport and agriculture, making risk assessment and adaptation strategies essential for resilience. Scientifically, understanding these scenarios improves climate models and informs policy decisions for sustainable development. Overall, anticipating and responding to rainfall changes is critical for managing interconnected environmental, societal, and economic challenges.

It is important to understand the precipitation change scenario for the following reasons:

a) Precipitation plays an essential role in the water resources available to meet our daily needs. It replenishes the water table and increases its content. Lack of knowledge of precipitation change scenarios can lead to the overexploitation of groundwater and jeopardize the availability of the resource.

b) According to the FAO, rain-fed agriculture produces 60% of the world's food. Understanding the pattern of rainfall change can help avoid agricultural production losses due to drought or waterlogging.

etc.