The water that replenishes groundwater, rivers and lakes is under threat from climate change, pollution and aging infrastructure.
When water turns from a gas into a liquid, it forms droplets. Whether those droplets are dew or rain depends on where the droplet forms.
It was the Seine’s rise and fall, in response to heavy rain, that inspired our current understanding of river systems.
To answer this question from Fiona, age 6, we need to know some things about clouds and light.
Natural variability alone does not account for observed changes in global (ocean and land) precipitation; rather, those changes…