Global Warming

[P_Rog]

Can global warming be attributed to the large increases in processes in today's world that produce heat. Every day things such as transporation, A/C, creation of electricity, all produce heat. Can this be linked to global warming?

[bloodhound]

global warming is just a definition i think. just to describe a situation where the heat from the sun is trapped in the earths atmosphere cos of greenhouse gases. dont know if it includes heat from earth

[NSX]

Can global warming be attributed to the large increases in processes in today's world that produce heat. Every day things such as transporation, A/C, creation of electricity, all produce heat. Can this be linked to global warming?

 

I think that's okay for the most part, though there are other factors that contribute to global warming besides our world's processes (e.g. cow burps).

[Ophiolite]

Can global warming be attributed to the large increases in processes in today's world that produce heat. Every day things such as transporation, A/C, creation of electricity, all produce heat. Can this be linked to global warming?

A simple calculation of the global energy generation versus solar energy input will show the very small role of the former.

Remember also that it is not so much heat generation that is responsible for global warming but heat retention.

[Primarygun]

Every day things such as transporation, A/C, creation of electricity, all produce heat. Can this be linked to global warming?

It is true.

Citizen indirectly increase the rate of G.W.

Carbon dioxide released from burning coal, the greenhouse gases and waste gases from vehicles are the sources of greenhouse gases in the troposphere.

[JohnB]

Carbon dioxide released from burning coal, the greenhouse gases and waste gases from vehicles are the sources of greenhouse gases in the troposphere.

Interesting proposition. Since it is known that the world was warmer 1,000 years ago than it is today, exactly what polluting vehicles were the Vikings using?

[coquina]

The first thing you have to do is separate natural global warming from anthropogenic human induced global warming. Here's a site from NASA with some good information on the latter:

http://www.giss.nasa.gov/research/features/altscenario/

 

Everybody talks about "global warming", but if you want to research the subject, the better term to google is "climate forcing".

 

It's important to understand that the climate is warming and sea level is rising regardless of man's influence, we are currently in the Hollocene Epoch (from the present to 11,000 years ago. Preceding that was Pleistocene Epoch (from 11,000 years to 2 million years ago. The Pleistocene had some of the most erratic climate changes in the history of the earth, and although humans were around during part of that period, they were not advanced enough to have influenced any of them.

 

Climate Change: Lessons from Geology and Complexity Science

(Author: L. Waite, Fall 2002

 

http://www.geocomplexity.com/global_climate_&_climatic_changes.htm

 

I just found this paper, and haven't read it through completely, but will print it out and study it this week end. Based on other papers I have read, it seems well put together and accurate.

 

You may wonder how we arrive at what the temperature was like millions of years ago. Oxygen Isotope analysis is one of the most important tools. I find it particularly fascinating and think this author has made as good an explanation as I have read, so I'll quote that snippet here:

 

Oxygen isotopes: the mother of all paleoclimate tools

 

 

 

Perhaps the most useful proxy of temperature and climate change over geologic time intervals

 

involves the analysis of oxygen isotopes. Oxygen has two important isotopic forms, light oxygen (O16)

 

and heavy oxygen (O18). The light form of the element occurs naturally in far more abundance than the

 

heavy variant; at present only about 1 atom per 1,000 atoms of oxygen consist of O18. The relative

 

abundance of light vs. heavy oxygen, measured in parts per million, can be determined very precisely

 

with use of a mass spectrometer.

 

 

 

The basic principle of the proxy relies on the temperature dependence of oxygen isotope fractionation

 

in the system CO2 – H2O – CaCO3 (Emiliani, 1966). As normal seawater evaporates, the heavier O18

 

molecules are preferentially left behind. Some of the light-enriched water vapor precipitates back into

 

the ocean; however, wind and clouds carry some amount over land. In cold weather regions, the light-

 

enriched water is deposited on land as snow, which with shallow burial, turns to ice. The ice therefore

 

contains a lower O18/O16 ratio than normal seawater. In other words, ice sheets are enriched in light

 

oxygen, and sea water, together with invertebrate organisms that secret a hard calcium carbonate shell

 

from seawater, are enriched in heavy oxygen. Scientists have discovered that the preferential evaporation

 

process not only depends on the original composition of the seawater, but on temperature as well, and

 

have shown empirically that a decrease in heavy oxygen of one part in one thousand equates to a drop

 

in surface ocean temperature of 1.5oC (~ 3oF). Ice cores have the added benefit of containing air bubbles

 

that trap atmospheric gasses such as methane and carbon dioxide, providing a direct measure of past

 

atmospheric composition.

 

 

 

Use of the oxygen isotope method provides a paleoclimate proxy that extends well beyond most other

 

indicators into the distant geologic past. However, as one delves further into the past, the original isotopic

 

composition of ancient seawater becomes more uncertain. For the deep past (i.e., > 2 mybp), it therefore

 

becomes increasingly important to combine isotope analysis with paleocontinental reconstructions and

 

other paleoclimatic indicators in the rock record such as the presence/absence of salt and anhydrite,

 

carbonate, coal, tropical plants, etc.

 

 

 

One of the first analysis of past temperature variations in the middle northern and southern latitudes, as

 

indicated by oxygen isotopes, suggested that large portions of the Earth during the Mesozoic Era were

 

much warmer than today (Emiliani, 1966). In hindsight the profile also suggests that large climatic swings

 

occur over relatively short time periods. It took several decades of subsequent climate study, including the

 

retrieval of ice cores from the Arctic, to fully appreciate the rapidness in which the global climatic state

 

can change.