What is the percetage of co2 in the Earths atmosphere?

Question

My understanding was that it was 0.038% but the answer to this question suggests it is 0.00038

http://answers.yahoo.com/question/index;_ylt=AtiP0WZKX.GM5W9ivjvbZloS.Rd.;_ylv=3?qid=20080822074657AA0yECx

Answer 1

The percent sign (%) means 1/100th.

380 parts per million (the amount of CO2) can be written as 0.000380 or 0.038%.  They are equal values.

Answer 2

It is 380 ppm and then convert that to percent of the atmosphere is .000,380% ,which is nothing.An example there is 20.9% oxygen.  

Answer 3

I have actually seen a slightly higher figure of 0.054% of all greenhouse gasses, I presume its higher as it accounts that not all gasses in the atmosphere are greenhouse gasses.

Either way, co2 is a mild greenhouse gas and only a tiny part of the greehouse effect. Water vapour is the main greenhouse gas that keeps the earth warm, not co2. co2 historically seems to have had no impact on temperature and many people believe its effect is actually neutral.

Answer 4

"I have actually seen a slightly higher figure of 0.054% of all greenhouse gasses, I presume its higher as it accounts that not all gasses in the atmosphere are greenhouse gasses."

It is difficult to get the percentage of greenhouse gasses for CO2, as water vapor's concentration is so variable.

Ken pretty much answered this. The various ways of denoting CO2's concentration:

1) 0.00038 as a decimal (parts per one)

2) 0.038 as parts per hundred (0.038%)

3) 0.38 as parts per thousand (0.38‰)

4) 3.8 as parts per ten thousand (3.8‱)

5) 38 as parts per one hundred thousand (38pcm)

6) 380 as parts per million (380ppm)

Generally, 2 and 6 will be the most common ways you will see the concentration, especially 6.

Answer 5

.038% is the same number as .00038. That number seems really small, but it is responsible for keeping our temperature normal, and adding even a small amount more can severely affect that.

Answer 6

Subject: IT IS NOT GLOBAL WARMING, BUT IT IS A SHIFT IN CLIMATE ZONES DUE TO THE DECREASE IN THE EARTH'S OBLIQUITY

> The earth's obliquity Angle decreases by 0.47" each

> year, which changes the focus of the sun's radiation

> on earth, resulting in climate shifts. As the

> obliquity angle decreases, the hemispheres change in

> basic temperature with the south becoming colder and

> the north becoming warmer.  When the obliquity angle

> reaches about 22 degrees, it will start to go the

> other way and the north will get colder again and the

> south will become warmer.  Obviously, and counter to

> Al Gores unlearned theories, the warming of the

> northern hemisphere cannot be stopped by man.  It will

> stop and reverse itself.  Then the climate shifts we

> presently experience will be goin the other way.  It

> is pure logic applied to astro-physical law.

>

> It has long been recognized that rather than staying

> constant, obliquity varies slowly with time as a

> result of external gravitational influences. The Moon

> and Sun's tidal torques on Earth's ellipticity give

> rise to the familiar 26,000-year astronomical

> precession, while the gravitational pull of other

> planets, primarily Jupiter and Venus, slowly perturbs

> the orientation of the ecliptic plane in space. The

> combined effect observed by Earth dwellers is an

> ~41,000-year oscillation in the obliquity with overall

> amplitude typically of about 2°. This oscillation is

> one of the three Milankovitch cycles that ultimately

> affect our long-term climatic system and serve as the

> pacemaker of ice ages. The present-day obliquity

> happens to be close to the mean value, and we are in

> the middle of a downswing (see figure (1)). In terms

> of real distance on the Earth's surface, one should

> see a slow equatorward shift of the tropics by 14.4 m

> a year-well over 1 km in a century!