CO2: Endless warming

Carbon dioxide is the number one reason for man-made climate change. But what is carbon dioxide, and why is it harmful?
Protestors dressed in CO2 molecule costumes, demonstrate in Essen, Germany, as part of the .../ Credits: Reuters

Contribution to Human-Induced Climate Change: 70 percent
Global Warming Potency (100 years): 1 (benchmark to other gases

Carbon dioxide is the second most important greenhouse gas behind water vapor, but the most important contributor to anthropogenic climate change. Methane and ozone are more potent, but have less effect on climate change due to their smaller atmospheric concentrations.

The amount of carbon dioxide (CO2) in the atmosphere has been in flux throughout the Earth’s history, but the United Nations Intergovernmental Panel on Climate Change (IPCC) estimates that in pre-industrial times CO2 made up around 280 ppmv (parts per million volume) of the Earth’s atmosphere.

Since the beginning of the Industrial Revolution, however, the average amount of carbon dioxide in the atmosphere has increased by nearly 40 percent from an estimated 280 to more than 380 ppmv.

Carbon dioxide has always been with us. Scientists say Earth’s earliest atmosphere was made up mostly of steam, carbon dioxide, and ammonia from volcanic eruptions.

Today, carbon dioxide is naturally produced by the combustion of organic matter like coal, oil, and wood, and the fermentation or respiration processes of living organisms.

People are another source. The air we exhale is made up of about 4.5 percent CO2. Bacteria in the soil release CO2 when they digest leaves and carcasses. Even plants that usually absorb CO2 'exhale' it at night.

Role and Uses

CO2 is one of the most important substances on Earth. Besides providing warmth to the world, it is the world’s most important fertilizer.

Plants, phytoplankton, and algae need the gas for their photosynthesis to produce sugar and to grow. While doing so they absorb and bind carbon dioxide and produce oxygen. That is why forests are one of the world’s most important absorbers of CO2, otherwise known as 'carbon sinks'.

There are a number of artificial uses of carbon dioxide, in fire extinguishers, as dry ice and, as the food additive E290, CO2 adds the fizz to soft drinks and sparkling water.

The increase in CO2’s share of the atmosphere is mostly due to anthropogenic (man-induced) factors, such as burning fossil fuels, deforestation, and industrial production.

Most anthropogenic CO2 is produced by energy production and transport. Cement production is just one among many chemical processes that release the gas. Rotting organic materials release CO2, and so landfills are big CO2 contributors too.

In total, humans emit around 32 gigatons of carbon dioxide each year. Half of this stays in the atmosphere; the rest is absorbed by oceans and vegetation.

But with sharp increases in man-made CO2 emissions, the natural CO2 cycle has been thrown out of balance: vegetation can no longer transform the same proportion of CO2 into oxygen, and oceans are steadily reaching saturation level.

Theoretically, rising CO2 levels should be compensated for by plants and algae. Up to a certain concentration, more CO2 means more photosynthesis and more growth.

Unfortunately, under hot and dry conditions many plants close their pores to prevent the loss of water and switch to a process called photorespiration during which they consume oxygen and produce carbon dioxide. Only areas with enough precipitation and fertile soils will see increased growth as a result of rising CO2 levels.

The result is an enhanced greenhouse effect and, subsequently, climate change. While CO2 is only responsible for 20 percent of the natural greenhouse effect, it accounts for about 60 percent of the anthropogenic greenhouse effect that is causing the current global warming.

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Comments (27)

SandySan: 19.01.2014, 12:45

The Earth produces more CO2 than anything any humans can produce and has for thousands of years increased and decreased this activity. One volcanic eruption would erase anything any humans could attempt to do to decrease CO2. We are merely little ants on this great planet. And if all humans were to die off tomorrow, not a single thing would change on this Earth.

AdamEve: 05.05.2013, 05:49

dev dongol, crawl back to your hole: Climate change is real; however, you aren't. Probably a paid Republican.

dev dongol: 30.12.2012, 07:17

This is a false, pseudo science. Climate change or global warming due to gases is imppossible. Gases are helping the earth to cool down by convection method of heat transmission. Gases can't form a green house, so no GHE and NO GHG. for details please visit my blog - devbahadurdongol.blogspot.com - the blog has email address also.

Conservative Caveman: 07.11.2011, 03:04

Follow the money....
RGGI, Chicago Climate Exchange

"Climate Change" is all about money, nothing else
Just another liberal redistribution of wealth plan from advanced countries
to third world countries.
China lights up a new coal plant every week.
The overreaching EPA has virtually put a stop to any new exploration in this country
Everyone else is allowed to explore for more fossil fuels except the US. Why?
Redistribution of wealth.

People like hypocrite Al Gore stand to make billions off of this scam
Al lives in a house big enough for 10 families

I've seen government make modeling show the results that they want.
I could do the same.

In a nut shell the earth has been warming and cooling since day one.
Nothing man does would ever change that.

dev dongol: 17.08.2011, 16:01

climate change and unlimited hydropower

dear SIR/ Madam,

it is stupid to blame gases for green house effect or climate change.
there is no scientific, not a single, principle to support
baseless blame. it is impossible to have green house effect due to gases
which are freely moving molecules. they are actually helping the earth
to cool down. for details (10 scientific reasons to prove the accusation is wrong)
please.I have explained the cause of climate change.

visit: devbahadurdongol.blogspot.com

i have also shown in the blog the blunder in hydropower engineering. the correction of the
mistake can give us unlimited hydropower.

at present in the world we are harnessing only minimum hydropower
from the already installed infrastructures because we applying property
of standing still water column in the water running condition.



for ways to harness unlimited hydropower.

Earth is blessed with unlimited hydropower.

email: dev.dangol@yahoo.co.uk


mushroom: 31.07.2011, 13:28

This explains a lot.

skeptik: 29.07.2011, 13:52

“NASA satellite data from the years 2000 through 2011 show the Earth’s atmosphere is allowing far more heat to be released into space than alarmist computer models have predicted… the study indicates far less future global warming will occur than United Nations computer models have predicted, and supports prior studies indicating increases in atmospheric carbon dioxide trap far less heat than alarmists have claimed.”

manno_sweety: 24.03.2011, 09:30

Right now the centre of focus is just reducing CO2 emissions or create areas that would "take in" this gas and atleast bring a little bit of change.
Afforestation (planting trees) can help alot in the global warming phenomenon. I belive that natural wasy to prevent CO2 emissions are more effective then the artificial ways

Dhananjay Jog: 25.09.2010, 14:40

I think Carbon Capture and Storage (CCS) is the key enabling technology for a future in which we can continue to use our vast coal resources and also protect the climate.
No doubt CCS is not yet much developed but many corporates are optimistic about its advancement.

Dhananjay Jog: 25.09.2010, 14:30

The most significant challenge in addressing global climate change is reducing greenhouse gas emissions resulting from coal. Rising energy demand will continue to drive up coal consumption. Moreover coal is cheap, so it is being used to a greater extent by power plants.

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