Aug 25, 2009
”Global-warming” – Make your own prediction
This simple tool from SPPI (Science and public policy Institute) helps you find out the manmade warming at anytime in future. The excerpt below has been taken from july report on co2 by SPPI.
“‘Here is a step-by-step, do-it-yourself ready-reckoner which will let you use a pocket calculator to make your own
instant estimate of global temperature change in response to increases in atmospheric CO2 concentration.
STEP 1: Decide how far into the future you want your forecast to go, and estimate how much CO2 will be in the atmosphere at
that date. Example: Let us do a forecast to 2100. The Monthly CO2 Report charts show CO2 rising to C = 575 parts per
million by the end of the century, compared with B = 385 parts per million in late 2008.
STEP 2: Next, work out the proportionate increase C/B in CO2 concentration. In our example, C/B = 575/385 = 1.49.
STEP 3: Take the natural logarithm ln(C/B) of the proportionate increase. If you have a scientific calculator, find the natural
logarithm directly using the “ln” button. If not, look up the logarithm in the table below. In our example, ln 1.49 = 0.40.
STEP 4: Choose a climate sensitivity coefficient c from the table here
STEP 5: Find the temperature change ΔT by multiplying the natural logarithm of the proportionate increase in CO2
concentration by your climate sensitivity coefficient. In our example, we’ll chose the SPPI central estimate c = 2.50 F. Then –
ΔT = c ln(C/B) = 2.50 x 0.40 = 1.0 F°, your predicted manmade warming to 2100. It’s as simple as that!”
