| Yes. Even though an increase of a few degrees in global average temperature does not
sound like much, global average temperature during the last ice age was only about 4 to
5 °C (7 to 9 °F) colder than now. Global warming of just a few degrees will be associated
with widespread changes in regional and local temperature and precipitation as well as
with increases in some types of extreme weather events. These and other changes (such
as sea level rise and storm surge) will have serious impacts on human societies and the
natural world. Both theory and direct observations have confirmed that global warming is associated with greater warming
over land than oceans, moistening of the atmosphere, shifts in regional precipitation patterns and increases in
extreme weather events, ocean acidification, melting glaciers, and rising sea levels (which increases the risk of
coastal inundation and storm surge). Already, record high temperatures are on average significantly outpacing
record low temperatures, wet areas are becoming wetter as dry areas are becoming drier, heavy rainstorms
have become heavier, and snowpacks (an important source of freshwater for many regions) are decreasing.
These impacts are expected to increase with greater warming and will threaten food production,
freshwater supplies, coastal infrastructure, and especially the welfare of the huge population currently
living in low-lying areas. Even though certain regions may realise some local benefit from the warming, the
long-term consequences overall will be disruptive. |