One thing that will not be addressed in Copenhagen is the damage done by an ever growing human population on the natural balance of the Earth. This is the real elephant in the room which eventually we must have to face up to. Even if we eliminate completely CO2 emissions from energy production by developed countries we humans will continue to degrade the earth while our numbers increase.
These are the back of the envelope calculations of Mankind’s emissions of CO2 resulting just from there being 7-9 billion of us on the planet whether we burn fossil fuels or not.
1. Breathing : People on average breath in about 7 litres a minute of air. The air we breath out contains 4% CO2. In affect we are burning food(carbon) in oxygen to provide the energy to keep warm and active. Each one of us therefore emits about 0.3 liters of CO2 a minute weighing 0.6 gm, or 0.3 tons of CO2 per year. The current population is 7 billion and UN forecasts a population of 9-10 billion by 2100. Lets take a nice round figure of 10**10 people as the maximum human population. This gives:
Yearly CO2 emissions through breathing : 3 Gigatons/year
2. Domesticated Cattle breathing: Cattle are a key source of sustainance to many people throughout Africa and the rest of the world. The world populaion of domesticated cows is about 2 billion. Each cow produces about 1.5 tons of CO2 just by breathing. Methane emissions from cows humans and agricuture are completely ignored here
Yearly CO2 emissions through of domesticated cows : 3 Gigatons/year
3. Agriculture, Deforestation through burning and land clearance. As ever increasing numbers of people demand food more from the available arable land so the pressures on natural envirnments and especialy forests increase. Forests are a key sink of the carbon cycles.
Figures resulting from deforestation from FAO : 2-4 Gigatons CO2/year
4. Finally the emissions of CO2 from Burning of Fossil fuels by developed and developing nations - Industrialisation. The agreements hoped to be reached in Copenhagen focus entirely on man-made (western industrial) induced emissions of CO2 high energy production. The current global figures for all CO2 emissions caused by the burning of fossil fuels in 2008 is:
Yearly emissions fossil fuels: 5 Gtons CO2/year.
There are important measures that can be agreed in Copenhagen to reduce emissions of CO2 by industrialised countries. Yet these can only delay catastrophy while population levels increase beyond sustainable levels.
We all know the theory. The average temperature of the Earth would only be about 6 degrees C. if it had no atmosphere. This temperature can be derived from Stefan Boltzman’s law assuming that the Earth is a perfect Black Body in thermal equilibrium with the Sun’s radiant energy. Luckily greenhouse gases in the Earth’s atmosphere actually keep the Earth’s temperature at a more comfortable ~ 15 degrees C. Human activity has led to an increase of about 25% in CO2 concentration in the Earth’s atmosphere and this is now predicted to increase average temperaturesby a couple of degrees over the next century. Glaciers will melt, sea levels will rise, people will migrate, our way of life is to blame - we must repent etc. So if all this is now accepted as factual evidence, then how come the desert is so cold at night ?
Temperatures in the Sahara and other deserts can reach 45 degrees during the day but then magically fall to below freezing at night. Now the CO2 concentration in the air is exactly the same over the Sahara as it is anywhere else e.g. in Hawaii where long term measurements are made. How does this magic work? - surely human additions to CO2 that we are so alarmed about must also cause greenhouse warming in deserts. The greenhouse effect acts like a blanket helping block infra red radiation losses to space and thereby keeps the Earth warm. So what is going wrong and why is it that the greenhouse effect simply doesn’t seem to work at all deserts ? The answer to this question is not only interesting scientifically but because it exposes a flaw in the selective use of data to overstate the climate change issue for political reasons.
The desert temperature falls dramatically at night simply because the air is dry. There is little water vapour in the air and it is water vapour which dominates all other greenhouse gasses thereby contributing about 75% of the greenhouse effect on planet Earth, while CO2 causes only 10% of the warming. The main reason for this discrepancy is that there is a tiny amount of CO2 in the atmosphere compared with the amount of water vapour. This is not about clouds which are another story - it is just about the number of H2O molecules in clear air compared to the number of CO2 molecules. The amount of water vapour in the air varies dramatically from the tropics to arctic and desert regions but on average it is about 1-4 % at the surface. CO2 is just 0.038% so at the surface there are about 100 water molecules for every CO2 molecules and averaged over the entire atmosphere there are at least 10 times more water molecules. Without water vapour the greenhouse effect would be at least one order of magnitude smaller, and the direct evidence for this are those very cold nights with sub zero tempreatures in the desert where the air is dry.
Water vapour is often taken out of the equation because it is a supposed feedback greenhouse gas. The air can hold more water vapour the warmer it gets so the argument goes that CO2 is the real driver for warming so that as the atmosphere warms it holds more water vapour thereby warming even more - a positive feedback. As air rises so it cools and given sufficient concentration water vapour condenses out as clouds at a certain height once it reaches the dew point. Clouds then can have two separate effects : 1) They reflect incoming sunlight back to space thereby cooling the land and 2) They reflect infra-red back to the earth thereby warming. During the day the former usually wins which is why it feels cold when the cloud blocks the sun and at night the second effect dominates keeping the land warmer than it otherwise would be. So it is not clear whether clouds warm or cool the Earth or whether they produce a negative or positive feedback. Imagine a world completely covered in white clouds. Would the temperature at the surface be higher or lower than today. My gut feeling is that it would be cooler as more of the sun’s energy would be reflected back to space.
