all of the water in the hydrologicalcycle --> how much water is stored in different stores and flows and how long it stays there
what does residence time mean?
the length of time a water molecule spends in a store on average --> some are very short e.g. just a few days in the atmosphere and others are long e.g. thousands of years in glaciers
water must be physically and economicallyaccessible for humans to be able to use it e.g. groundwater is hard to access so it may not be costeffective to extract it, this means only a small amount of water can be used by humans
how do resistance times affect the availability of water for human use?
water with shorter residence times tend to contain fewer pollutants, making it a bettersource of water for human use
water that's not been replenished for a very long time, due to its residencetime is called non-renewable water e.g. cryosphere and deep groundwater held in fossil water
what is fossil water?
an ancient body of water that has been contained in an undisturbedspace like an aquifer for many thousands of years
how have humans impacted the cryosphere?
climatechange and global warming = snow melts quicker, revealingdark surfaces --> this causes ice to melt quicker due to the albedo (reflectivity) changing as darker surfaces absorb more solar radiation --> positive feedback
we lose arctic ice at a rate of almost 13% per decade due to the albedo change, alongside warming oceans
