Page 38 - Alternative Energy Systems in Building Design

THE LITTLE ICE AGE 15

Figure 1.10 Great weather and flood and catastrophes over 40 years.
Courtesy of the United Nations Environmental Program/GRID-Arendal.

Other potential effects of global warming that have not yet been fully studied
include the potential to either inhibit or promote certain natural processes. For
instance, we do not know whether rising temperatures promote or inhibit vegetative
growth, which, in turn, could either absorb more or have a saturation level that will
decrease carbon dioxide levels. It should be noted that evidence for climate change in
the past has been taken from a number of sources, allowing for the reconstruction of
past climatic variations (Fig. 1.10). Most of the evidence gathered has been based on
indirect climatic changes inferred from changes in indicators that reflect climate, such
as pollens and fossilized remains of species.

The Little Ice Age

The following discussion outlines recorded historical global temperature variations
and their resulting consequences, which affected population growth and survival,
human health, nutrition, wars, and geopolitical events. Two principal climate changes,
the medieval climate optimum and the little ice age, are the basis of this discussion.
However, their existence is not entirely supported scientifically.
Medieval climate optimum refers to the global temperature elevation that resulted
from heightened solar flare activity from the tenth until the mid-thirteenth century.
During this time, most of the European continent experienced a period of elevated
temperature, resulting in population migration toward northern countries. It is at this