It is important to stress
how complex the climate challenge is and
how hard it is to predict with accuracy how
severe climate exposures facing populations
will become. There are many factors that
could slightly slow or significantly speed
up the rates of change, including positive
feedback effects and, most worrying of all,
cascading climatological tipping points. For
this reason, mitigating existing greenhouse
gas emissions (GHGs), as well as developing
and implementing measures to protect human
development from the changing climate, is
of paramount importance