Climate change
refers to the change in global climate patterns over the last century.
Most scientists
accept that it is a reality tied to carbon dioxide and other greenhouse
gases emitted their human activities, including the use of fossil fuels.
Greenhouse gases trap heat in the Earth's atmosphere, causing temperatures to rise.
In fact, the ten warmest years on record have all occurred since 1998.
So how did we get here in 1769?
James Lock's version of the steam engine was patented and this innovation
led to the widespread use of coal, a major fossil fuel, both then
and now to power industry, agriculture and textile production.
As a result, the productivity of these industries dramatically
increased in the period known as the Industrial Revolution.
Studies reveal the beginnings of a sharp increase in
CO2 in the Earth's atmosphere corresponding to this period.
Since then, engines powered by carbon based
fuels have proliferated in cars, planes and ships.
These fuels are used to generate power and manufacture goods to
activities beyond fossil fuel.
Use also generate greenhouse gas emissions.
Deforestation is one example.
Since trees absorb carbon dioxide The amount of CO2 in the atmosphere
is higher today than it has been for hundreds of thousands of years.
The effects are significant and include melting polar ice.
Rising sea levels.
Severe storms, droughts and flooding.
The consequences include widespread destruction,
particularly for those living in coastal areas and on islands.
The extinction of plants and animals.
Water scarcity and changing crop and fishery yields.
Climate change can contribute to hunger, refugee flows and more.
These consequences
will occur unevenly across time and place, but will affect everyone.
There is wide scientific agreement about the urgent need to address
climate change, but less political consensus about how
the possibilities can be grouped into three categories.
Mitigation, adaptation and geoengineering
mitigation refers to efforts to reduce or prevent emissions of greenhouse gases,
whether by increasing the efficiency of fossil fuel use
using cleaner fuels or preserving or replanting forests.
Electric and fuel efficient cars, mass transit
and bike sharing programs are all examples of mitigation efforts.
Energy use from fossil fuels is a major emission source
for reducing these emissions at a scale that prevents the worst effects
of climate change,
while providing the power necessary for a growing world is an enormous challenge.
There are two policy approaches for mitigation efforts top down and bottom up.
A top down strategy sets an overall international goal and assigns
each country a particular action to fulfill that goal.
A bottom up approach does not bind countries to specific steps.
The 2015 Paris Agreement, in which countries themselves decided
what mitigation actions to take, is one prominent example top down
agreements have proved harder to reach because countries disagree on
how to share the burden of cutting emissions.
Developed powers such as the United States and European countries,
major developing states such as China and India
and smaller developing countries all have differing views.
Another policy response is adaptation,
which aims to reduce the world's exposure to climate change's effects.
This includes moving people from areas prone to flooding and using barriers.
Regulations such as building codes and other steps to protect those who stay.
Large scale adaptation, including the relocation of entire island
countries, is expensive, and governments differ on who should pay.
A Third Policy Area.
Geoengineering aims to reverse climate changes effects such as by releasing
particles into the atmosphere to deflect some of the sun's rays.
But the science remains in development, and the effects are uncertain.
There is also no consensus on who would approve any such act.
Geoengineering is thus controversial but will likely remain a possibility
if climate change and its predicted effects, advanced
greenhouse gases, affect us all.
No matter where they are emitted, this problem and the threats it poses
require a response from governments, businesses and citizens worldwide.