What is global warming? This is a fair question, as much is
written and said about “global warming”. The term is often misused and
people tend ask questions like, 'do you believe in global warming?' This
is a bit like someone asking an economist, whether they believe in
inflation. It is difficult to know where to start when answering, What
is Global Warming? This is because there are other hidden questions
buried in the original one. Many people when asking the first question,
are often also wanting to know if the warming is attributed to human
activity (
anthropogenic
); are greenhouse gases building up in the atmosphere?; and is the
warming something they should be concerned about? The short answer to
all those questions is YES!
Climate change has become a big political issue and a great deal of
debate
continues about the solutions. One approach being considered to reduce
global carbon emissions is the idea of
contraction
and convergence
. Under this approach all countries would participate in a global
emission reduction with quantified emission targets.
Scientists use "global warming" in a precise way, to mean "a
tendency for the globe to warm over a given period". There is a great
deal of scientific study focused on climate change, and the majority of
scientists agree that the average
global
temperature
is increasing. Check out some definitions of global warming
here.
When
'What is Global Warming', is only part of the story and it
doesn't tell us when this might happen. What we do know is that global
warming has occurred in
the
past,
and it is also happening right now.
Undoubtedly the temperature of the globe has fluctuated since the
very beginnings of our planet. The real problem is not just the fact
that it is warming, but the rate at which it is warming. The ten warmest
years since global temperatures have been measured all occur within the
last 12-year period between 1997-2008*.
But that is the recent past, and scientists are suggesting that
the current rapid rate of warming has no parallel within the last
million years. Even when the globe did warm towards the end of an ice
age the process was very gradual, warming up over a period of about
5,000 years. Our Earth is heating up, and heating up quickly.
How
The atmosphere surrounding the earth is mainly composed of
Nitrogen (about seventy eight percent, and Oxygen (twenty one percent)
with water vapour and various trace gases making up the rest. There are
quite a few trace gases, such as; Argon, Carbon Dioxide, Neon, Helium,
Methane, Hydrogen, Nitrous Oxide and Ozone. These gases, are often
called
green
house gases
because during the day the earth soaks up heat, and these gases act
like a
greenhouse
trapping in the heat. Some of the heat is radiated back out into space,
and if weren’t for these gases things would freeze over during the
night. The issue of course is the increase in greenhouse gases, which is
trapping in more heat, and causing a rise in global temperature.
Why
The proportion of greenhouse gases has increased significantly
since the Industrial Revolution. Humans began burning
fossil
fuels,
(particularly coal) in a big way, to drive steam engines for industry,
and generate electricity. When fossil fuels are burnt or combusted,
carbon dioxide, methane and nitrous dioxide are given off as gases. In
addition to escalating coal use after the Industrial Revolution, came
the widespread use of another fossil fuel; petroleum for transport. At
the beginning of the 20th century, annual global oil output was about
150 million barrels of oil, now, that amount is extracted globally in
just two days. Burning fossil fuels releases billions of tonnes of
carbon dioxide that has been locked away in the Earth for millions of
years. Humans are adding billions of tonnes of carbon dioxide to the
atmosphere each year, and guess what? Carbon dioxide is a greenhouse
gas.
The rate at which the planet is warming is possibly the single
biggest challenge to ever face humanity. The
impacts
are likely to devastating, we need to act decisively, and
act
now.
A single web page cannot fully answer the opening question, what is
global warming? Following the links on this page will allow you to see
how complex and serious the issue of global warming is. So what is
global warming? It is a disaster of our own making, that's what. A smart
idea would be to stop cutting our forests down, but what if we had
algae farms
feeding of the coal stacks and made biodiesel and health foods?
* See report at http://data.giss.nasa.gov/gistemp/2008/
