Global Warming

[Hank49]

Off the top of my head:

2) The drying out of several of the worlds "bread baskets"

3) Increased weather severity, potentially combined with increased rates of storms

4) Mass extinction of animal and plant species

Because all of the climatic models agree that the warming we expect to see will have a net downward effect on crop production, not benefit. Keep in mind that the kinds of temperature changes we're talking about are not going to open up vast new area of the earth to farming. Instead we expect to see changes in rainfall and storm patterns, and unfortunately all evidence suggests that todays major agricultural areas are in for poorer growing conditions, not better.

Bryan

So we slowly change to aquaculture as a main food source.
Mass extinction...I know..it's a shame but at this pace, it's inevitable.
Rainfall? Warmer temps mean more oceanic evaporation doesn't it? That has to fall somewhere. Warm regions, the tropics, tend to be wet, cold regions more dry. Flood or drought conditions mean we need more water storage capacity, and hydro power. Sorry for the salmon and other organisms that can't make it back to their upland waters but.....
Some places may dry out, others will get wetter. Genetically improved, faster growing, intensive culture tolerant crops will need be developed, which is already happening.

Whether or not the climatic predictions are accurate or not, we'd best prepare for a big change because I don't think it's in our power, politically or physically, to stop the process.

 

[Tomeck]

I know we're chin deep in global warming rhetoric now, but can we talk about whether CO2 makes any difference at all? I haven't seen much concrete evidence of how much CO2 contributes to the "greenhouse effect". Computer models that predict warming do not model the atmosphere physically based on properties of CO2 and predict energy flow, they simply have a number that is typed in that is a scientist's best "guess" as to the relationship between CO2 concentration and warming.

CO2 has a very narrow absorption band, so it can only absorb about 8% of the blackbody radiation sent out from the atmosphere and Earth's surface no matter how much of it is there. Also, it absorbs completely within the atmosphere at those narrow absorbtion bands, so there is no IR "escaping" right now that would be held in the atmosphere longer by more CO2.

There's also the view that atmospheric CO2 is rising because of slightly higher ocean temps, which in turn dissolve less CO2.

Anyway here are a couple sites that discuss this:

Cold Facts on Global Warming

Nitty Gritty Perspective on Global Warming—the CO2 Absorption Spectrum.

By the way, anybody that assumes the "experts" always get it right, you've seen this right? DailyTech - Blogger Finds Y2K Bug in NASA Climate Data

From the site:

The warmest year on record is now 1934. 1998 (long trumpeted by the media as record-breaking) moves to second place. 1921 takes third. In fact, 5 of the 10 warmest years on record now all occur before World War II

You don't believe global warming? It's certain that CO2 is responsible, you can see Venus, a planet who has 95% of CO2 and the temperature is 900°F.

 

[SNorman]

The scientific consensus is that it does.
Your number here is wrong. Most of the earths heat is released as IR energy; 71% of which is absorbed (and eventually re-emitted) by the atmosphere. CO2's spectra overlies pretty much dead-on the peak emission wavelength of the earth, meaning it can absorb a lot of heat. Of the energy captured by the atmosphere, H2O accounts for 60% of the absorbency, CO2 for ~26% with methane, N2O and O3 making up the remainder

I'm sorry, I have to respecfully disagree. CO2 aborbs it's main peak of IR at 15µM in 10 meters of atmosphere. Other bands are absorbed within 300 meters.

Compared to entire blackbody IR spectrum:

I'm sorry, if you don't understand what this means you're going to have to either brush up on your physics or this debate is useless. CO2 absorbs a relatively small portion of IR released from the Earth. It cannot possibly aborb the entire blackbody spectrum so even if the atmosphere was 100% CO2 most of the radation would leave.

By the way do you know what context your numbers came from re: H2O being responsible for 60% of absorbency? The figures differ depending on atmosphere location (troposphere, stratosphere, etc). Most estimates I see of the atmosphere *as a whole*, including clouds (yes, people who want to skew statistics will list "water vapor" absorbency and leave out clouds) show 90% absorbtion by water and 10% CO2.

 

[SNorman]

Hardly. Current models represent some of the most complicated computer models yet devised by man, and with the exception of a few variables we cannot control (i.e. CO2 levels) are based on the known physics of the earth and its atmosphere. The "golden standard" of the day are general circulation models. These models take into account a broad range of factors from cloud formation, to precipitation, sea absorption/release of CO2, heat transfer in the atmosphere, effects of particulates, changes in solar intensity, changes in albedo, etc.

By the way, current models are unable to correctly show what temperature the Earth would be at with no GW gasses present.

 

[SNorman]

As far as crops being affected, how about this piece on "Global Cooling" in Newsweek, 1975:

http://www.junkscience.com/apr05/coolingworld.pdf


There are ominous signs that the Earth’s weather patterns have begun to change dramatically and that these changes may portend a drastic decline in food production – with serious political implications for just about every nation on Earth. The drop in food output could begin quite soon, perhaps only 10 years from now. The regions destined to feel its impact are the great wheat-producing lands of Canada and the U.S.S.R. in the North, along with a number of marginally self-sufficient tropical areas – parts of India, Pakistan, Bangladesh, Indochina and Indonesia – where the growing season is dependent upon the rains brought by the monsoon.


If you cry wolf enough times...

 

[SNorman]

You don't believe global warming? It's certain that CO2 is responsible, you can see Venus, a planet who has 95% of CO2 and the temperature is 900°F.

Venus is closer to the Sun than Earth and it's atmospheric pressure at the surface is 90+ ATM :no

 

[Tomeck]

Venus is closer to the Sun than Earth and it's atmospheric pressure at the surface is 90+ ATM :no

I know that Venus is a third closer to the Sun than Earth, but Mercury is twice closer of the Sun than Venus and the average temperature is "only" 354°F, because there is not CO2. Between 900°F on Venus and 80°F on Earth is a enormous difference! :no

 

[drbill]

Given that the data appear to suggest that the ice sheets which previously covered the planet periodically throughout its known history were rather substantial, extending nearly to the equator in some instances and of significant thicknesses, what melted them?

Mankind's influence had yet to manifest itself.

It would appear that throughout the planet's history periods of intense cooling have been followed, cyclically, by periods of intense warming.

Allowing for even significant climatic degradation recently caused - to some extent - by mankind's deplorable abuse of natural resources, could it not also be that a cyclical period of warming may also naturally be occurring?

Global warming and cooling are part of natural cycles, with these changes occurring on time scales far in excess of those we are currently experiencing. It is not that global climate is warming that is important... it is the rate at which it is warmong.

The current rate of change is highly accelerated, with the other natural phenomena I can think of that would induce even more rapid rates being asteroid impacts (which would lead to different temperature changes), or possibly large-scale volcanic activity.

Ice masses can form or melt over periods of tens of thousands to millions of years. These changes are slow relative to what we are experiencing now.

 

[SNorman]

I know that Venus is a third closer to the Sun than Earth, but Mercury is twice closer of the Sun than Venus and the average temperature is "only" 354°F, because there is not CO2. Between 900°F on Venus and 80°F on Earth is a enormous difference! :no

Mercury has almost no atmosphere at all. Venus has an atmospheric pressure equal to almost 1000 meters deep in the ocean. If its atmospheric makeup (O2/N2/CO2/etc) was equal to Earth's, do you think the temperature would be similar, despite how thick the atmosphere is?

If both planets had equal amounts of atmosphere and one was purely CO2 and the other was O2/N2 you could do a fair comparison. What you're saying is like comparing a Ferrari and a Yugo and saying the Ferrari is faster because it's red.

 

[Eris Lucan7*]

Teta Gamma or Deta waves???

E.L.7*