I was wondering if I could get some expert opinion on this issue. If you know a lot about the subject or have degrees in climatology, then this thread is for you. I was wondering if you could answer a couple of questions that I have.
Richard, I am not a climatologist but I am an interested observer. Here's some info as I understand it.
FIRST: a few helpful links:
Realclimate.org: Several real climatologists discuss the science behind global warming.
"
How to Talk to a Global Warming Skeptic": a nice explanation of global warming skepticism points and rebuttals.
1. How much would you say humans contribute to the rising average temperature of the earth compared to "natural" causes. (IE. Solar Variation)
This is, as others have said, somewhat difficult to quantify but models using
hindcast data (data from the past that has already occured) show better fits with "human activity" factors in the model than natural factors only (
LINK)
The current level of CO2 in the atmosphere is significantly higher than it's been in 15 million years and studies of
isotopic make -up of the CO2 indicate humanity is responsible for a large portion of that recent run up (
LINK1,
LINK2,
LINK3)
2. Do you believe that the human contributions to the rising average temperature need immediate attention and immediate action?
Many of the experts in the field feel immediate action is the only answer. Hansen from NASA may be one of the louder of these experts, but he did indeed predict in 1988 some of the trends that came to pass in the ensuing 12 years based on his model inputs.
3. Do you believe that it's possible to change the current trend in the rise of average global temperature? By what means?
Apparently we are still able to change the trend but because CO2 has long "residence time" or "lifetime" in the atmosphere it will take some time for it to come back down. There's a "lag" in response because of natural CO2 cycling into and out of the atmosphere.
The main things we'll have to do is scale back, significantly, our combustion of carbon-based fuels and other materials that put other greenhouse gases into the atmosphere.
When I saw Hansen speak here in California a year or two ago he was talking about some drastic measures to get away from coal fired powerplants that will likely not be too palatable to the general public. I am unsure of what the best middle road is in some of this
4. If Anthropogenic Global Warming needs immediate attention, do you think that government intervention (IE. Kyoto Protocol) is a better solution than solutions that the market could offer?[/quote]
Unfortunately the only thing that will likely really have any effect is concerted, immediate effort. The downside is that that is hard to do without government mandate. THe even worst side is it is hard to enforce globally.
In the end onl we can control ourselves. Action at a local level is where it has to start. Action at a global level is where it has to go.
Just my dos centavos.