CLIMATE CHANGE
Climate change is happening
Our Earth
is warming. Earth's average temperature has risen by 1.5°F over the past
century, and is projected to rise another 0.5 to 8.6°F over the next hundred
years. Small changes in the average temperature of the planet can translate to
large and potentially dangerous shifts in climate and weather.
The
evidence is clear. Rising global temperatures have been accompanied by changes
in weather and climate. Many places have seen changes in rainfall, resulting in
more floods, droughts, or intense rain, as well as more frequent and severe
heat waves.
The
planet's oceans and glaciers have also experienced some big changes – oceans
are warming and becoming more acidic, ice caps are melting, and sea levels are
rising. As these and other changes become more pronounced in the coming
decades, they will likely present challenges to our society and our
environment.
Global
warming refers to the recent and ongoing rise in global average temperature
near Earth's surface. It is caused mostly by increasing concentrations of
greenhouse gases in the atmosphere. Global warming is causing climate patterns
to change. However, global warming itself represents only one aspect of climate
change.
Climate
change refers to any significant change in the measures of climate lasting for
an extended period of time. In other words, climate change includes major
changes in temperature, precipitation, or wind patterns, among other effects,
that occur over several decades or longer.
Humans are largely responsible for recent
climate change
Over the
past century, human activities have released large amounts of carbon dioxide
and other greenhouse gases into the atmosphere. The majority of greenhouse
gases come from burning fossil fuels to produce energy, although deforestation,
industrial processes, and some agricultural practices also emit gases into the
atmosphere.
Emissions
at sunset Greenhouse gases act like a blanket around Earth, trapping energy in
the atmosphere and causing it to warm. This phenomenon is called the greenhouse
effect and is natural and necessary to support life on Earth. However, the
buildup of greenhouse gases can change Earth's climate and result in dangerous
effects to human health and welfare and to ecosystems.
The choices
we make today will affect the amount of greenhouse gases we put in the
atmosphere in the near future and for years to come.
Climate change affects everyone
Our lives
are connected to the climate. Human societies have adapted to the relatively
stable climate we have enjoyed since the last ice age which ended several
thousand years ago. A warming climate will bring changes that can affect our
water supplies, agriculture, power and transportation systems, the natural
environment, and even our own health and safety.
Some
changes to the climate are unavoidable. Carbon dioxide can stay in the
atmosphere for nearly a century, so Earth will continue to warm in the coming
decades. The warmer it gets, the greater the risk for more severe changes to
the climate and Earth's system. Although it's difficult to predict the exact
impacts of climate change, what's clear is that the climate we are accustomed
to is no longer a reliable guide for what to expect in the future.
We can
reduce the risks we will face from climate change. By making choices that
reduce greenhouse gas pollution, and preparing for the changes that are already
underway, we can reduce risks from climate change. Our decisions today will
shape the world our children and grandchildren will live in.
