Pelican Parts Forums

Pelican Parts Forums (http://forums.pelicanparts.com/)
-   Off Topic Discussions (http://forums.pelicanparts.com/off-topic-discussions/)
-   -   800,000 Year Record Of Atmospheric CO2 (http://forums.pelicanparts.com/off-topic-discussions/302742-800-000-year-record-atmospheric-co2.html)

jyl 09-05-2006 11:28 AM

800,000 Year Record Of Atmospheric CO2
 
I don't pretend to know much about the scientific basis of the global warming debate, but I am trying to educate myself. So this news story caught my eye.

http://www.washingtonpost.com/wp-dyn/content/article/2006/09/04/AR2006090400451.html

http://news.bbc.co.uk/2/hi/science/nature/5314592.stm

I'll summarize:

For the past 800,000 years, CO2 concentration in the atmosphere has ranged from 180ppm to 300ppm. The level today is 380ppm.

In past periods of rising CO2 levels, the rise was very slow, 30ppm per 1000 years. In the past 200 years, CO2 levels have risen very fast, by 100ppm.

The increased CO2 is from fossil fuel origin.

Anyone have good, readable, fact-based URLs to share, on the issue of global warming's cause, existence, and effects, or conversely the lack of same?

legion 09-05-2006 11:35 AM

1) How do we know what the atmospheric CO2 level was 800,000 years ago? We've only been measuring it since the 1950s.

2) Volcanoes put out more CO2 every year that all human activitiy combined...and I'm talking a scale of magnitude more. Was it a very active year for volcanoes?

What I'm getting at is these alarmist news articles usually leave out a whole bunch of directly relevant information.

jdm61 09-05-2006 11:43 AM

It is measured using core samples of ice, dirt, rock,etc from the time period we are looking at. You should see if you can find some figures on what it was 65 million years ago when the oxygen content of the atmosphere was much higher than it is now. In the late Cretaceous period, you had temperate climates in places in Alaska and Northern Canada where you know have sub-arctic tundra. The question is not whether climate changes......it does. We are not that far out of the 'little ice age" that lasted for several hundred years and only about 12,000 froma MAJOR ice age that saw glaciation all the way to the Ohio River valley. The question is what effect, if any, we are having and how much.

nostatic 09-05-2006 11:43 AM

you can measure atmospheric CO2 levels by looking at ice cores

http://www.earthsky.org/shows/edgeofdiscovery.php?date=20041129

legion 09-05-2006 11:50 AM

Quote:

Originally posted by nostatic
you can measure atmospheric CO2 levels by looking at ice cores

http://www.earthsky.org/shows/edgeofdiscovery.php?date=20041129

I realize that; I'm just trying to introduce the idea that there is an often overlooked difference between direct measurment and infering a measurement based on studying something else.

Let me put it to you this way: What would hold up in court? A cop giving you a speeding ticket based on measuring your speed with a radar gun, or a cop giving you a speeding ticket based on his estimation of the speed you were going based on engine noise with his back turned to you...

carnutzzz 09-05-2006 12:21 PM

CO2 isn't much of a greenhouse gas.

Methane- now that is a greenhouse gas.

red-beard 09-05-2006 12:48 PM

Water-vapor is a better greenhouse gas

Moneyguy1 09-05-2006 01:37 PM

There cannot be an 800,000 year record of anything...

Don't the creationists peg the age of the earth at something around 6,000 years?

Motion....P.S. The trapped gases and sediments in ice cores are quite accurate. Tests done on samples that can be corroborated over the past 50 years show the degree of accuracy. Things like Krakatoa, Pompeii and such, actual historically recorded events can be found in these cores.

Moses 09-05-2006 02:27 PM

Maybe if we all hold our breath for a few seconds. OK,...NOW!

widgeon13 09-05-2006 02:32 PM

Make farting a punishable offense......:eek:

ckissick 09-05-2006 02:39 PM

All I know about this is what I read, and two things worth noting are:

1) I've read that ice core data are, in fact, quite inaccurate. When you de-pressurize the air sample, its chemistry changes. Other errors comes in during sampling amd handling. Therefore, the results have a plus/minus component, and the alarmists just report the lower end of the error scale. The upper end of the error scale gets you well above 300 ppm.

2) Even if we have caused CO2 levels to go higher than anytime in the last 800,000 years, some climatologists say, "So what?" CO2 has a very small role in global warming, with maybe 2.5% of warming attributed to CO2. Water vapor is by far the most important green house gas, as red-beard alluded.

jyl 09-05-2006 02:42 PM

Quote:

Originally posted by legion
I realize that; I'm just trying to introduce the idea that there is an often overlooked difference between direct measurment and infering a measurement based on studying something else.

If you insist that all measurements be "direct" rather than "inferred/indirect", then you cannot believe in the majority of modern physics and a substantial amount of current technological achievements.

The mass of planets, stars, etc is measured from observing their effect on other things, e.g. light rays and other bodies. Obviously - we can't drop Jupiter on a bathroom scale. But NASA can slingshot probes around distant planets thanks to these indrect measurement.

The behavior and existence of subatomic particles is determined from observing their interaction with other particles via collision, decay, energy release, etc. A quark doesn't show up directly on a photographic plate.

And so on.

So, I see no reason to disbelieve scientific investigation simply because it uses indirect measurements.

Anyway, are the measurements taken from these deep cores really "indirect"? As I understand it, they are extracting and measuring the actual atmosphere that was trapped in arctic ice layers as they formed 800,000 years ago.

[Edit - as just pointed out, I guess any type of measurement has to be examined for experimental error. I imagine you should take numerous measurements from a given depth and look at how consistent or inconsistent the results are.]

jyl 09-05-2006 02:54 PM

Quote:

Originally posted by legion
Let me put it to you this way: What would hold up in court? A cop giving you a speeding ticket based on measuring your speed with a radar gun, or a cop giving you a speeding ticket based on his estimation of the speed you were going based on engine noise with his back turned to you...
This makes me realize that what is "direct" and what is "indirect" depends on how technologically advanced the period is.

50 years ago, the cop with this radar gun would never have been considered a "direct"measurement, much less allowed in court. "Direct" speed measurement would have meant timing the car over a measured mile, no ifs ands or buts.

But after 50 years experience w/ radar we now think of the radar gun as a direct measurement.

sammyg2 09-05-2006 03:02 PM

I question the results and the measurment techniques.
Another question, how do they know this isn't part of a normal cycle?
They say we are transitioning out of an ice age, is this a normal cycle?

What about the late 17000s when they say we had a mini ice age?

I say we don't have enough long term information to answer those questions or to panic over a theory that global warming is a result of man's interference. i suggest there may be alterior motives or possibly a bunch of jumping on the bandwagon going on.

Dixie 09-05-2006 03:28 PM

Quote:

Maybe if we all hold our breath for a few seconds. OK,...NOW!
Heck, that will never work.

Here's the real solution. Pick one day where everyone turns on their A/C and opens all the doors and windows.


Problem solved....

Tervuren 09-05-2006 03:42 PM

Quote:

Originally posted by Moneyguy1
There cannot be an 800,000 year record of anything...

Don't the creationists peg the age of the earth at something around 6,000 years?

Motion....P.S. The trapped gases and sediments in ice cores are quite accurate. Tests done on samples that can be corroborated over the past 50 years show the degree of accuracy. Things like Krakatoa, Pompeii and such, actual historically recorded events can be found in these cores.

I'd say humans cant' be much older then 8,000 years, but as to how old the universe is - beats me.

Tervuren 09-05-2006 03:45 PM

Quote:

Originally posted by Capt. Carrera
Heck, that will never work.

Here's the real solution. Pick one day where everyone turns on their A/C and opens all the doors and windows.


Problem solved....

Hehe.

I heard a story of a boss who put a bunch of portable AC units into the server room.

john70t 09-05-2006 04:26 PM

1. No, global warming is a myth, a scare tactic
2. O.k. there could be, but it's all a natural cycle
3. O.k. there could be, but the causes are, and will remain, uncorrelated, much like cigarettes and cancer
4. Yes there is, and you should thank us for doing it. Earth is too cold anyways.

trekkor 09-05-2006 05:08 PM

Yep, the age of the earth and universe is unknown to man.

800,000 years is just a guess. Another guess...


KT

Moneyguy1 09-05-2006 06:08 PM

And all the fossils were placed there to fool us and take us down the wrong road.

We have been given brains and logic, and clues to follow. If we decide to ignore these, we do so at our own peril.

My own take is a simple one: Nothing is impossible. Improbable, yes, but not impossible. If one wishes to enter religion into the equation, declaring something impossible would limit the power of a Creator.


All times are GMT -8. The time now is 11:03 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website


DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.