ur climate is heating up—
not of its own accord but
rather as a result of the
greenhouse effect: the
warming of the Earth’s
surface. As the amount
of carbon dioxide in the
atmosphere continues to
increase, the gas traps
more and more solar radiation, resulting
in more heat. Carbon dioxide is around
1,000 times more prevalent than the other
greenhouse gases and is considered to be
a major threat to our continued existence.
But is that really the case?
For an individual, CO 2 poisoning occurs
when the concentration of the gas in the
air rises to 10% or more. This can cause
unconsciousness and ultimately death
due to ventilatory failure. Under normal
circumstances that’s not a problem: The
CO 2 concentration in the air is ordinarily far
lower, though people who work in confined
spaces are vulnerable to CO 2 poisoning.
The effect of CO 2 on the climate is far
more insidious. Studies show that global
warming has resulted in more frequent
instances of extreme weather—and higher
numbers of deaths are often the result.
When air temperatures are warmer, cloudshold more moisture and energy, resulting
in higher levels of precipitation along with
more frequent storms and flooding. Other
climate-related events are droughts and
heat waves: During Europe’s summer heat
wave of 2003, record high temperatures
resulted in at least 30,000 deaths. And in
recent years annual wildfires have raged
out of control, in places such as Southern
California and currently in Australia.
The National Oceanic and Atmospheric
Administration says the global mean sea
level has risen about 9 inches since 1880,
with a third of that occurring in the last two
decades, leading to more extreme weather.O
JUST HOW DANGEROUS
IS GLOBAL WARMING?
200
million or more people will be displaced
by climate change by 2050. According to
the United Nations, that’s “one out of
every 45 people who will be alive at
the time.” This is an enormous
increase over the already
appreciable numbers
affected today.