 Figure 1b. A large amount of
observational evidence besides
the temperature records shows
that Earth’s climate is changing.
For example, additional evidence
of a warming trend can be found
in the dramatic decrease in the
extent of Arctic sea ice at its
summer minimum (which occurs
in September), decrease in spring
snow cover in the Northern
Hemisphere, increases in the global
average upper ocean (upper 700 m
or 2300 feet) heat content (shown
relative to the 1955–2006 average),
and in sea-level rise.
Source: NOAA climate.gov |