Jump to content
Science Forums

My belief in Global Warming is getting shaky


engineerdude

Recommended Posts

More than enough research has been done. People currently have nothing to do with global climate. On the other hand, we destroy coral, pollute rivers, erode topsoil, plenty of very real things. You are wasting your time and effort with imaginary problems like global warming. And you are in fact hurting the planet by diverting money and energy to pretend-issues things like AGW, instead of actually helping our world be better. In my opinion.

 

And I will be happy to continue trying to convince you all of this, people I respect, and who's opinions I value.

OK we have established we are both concerned about environmental degradation.

I see where you are coming from. Although I don't believe we can afford it to be an "either" , "or" problem. We have to fix all the environmental problems we have created.

Remember this is a very new concept down to Rachel Carson 30 years ago- max.

 

I too have doubts, and did not believe in global warming a few years ago.

Global modelling is very imprecise- look at the daily ,weather forecast!

If you listen to some of the links I gave, some support your point of view.

 

What is especially worrying is the state of the debate- when people can get environmental prizes for getting people to turn of city lights for an hour.!!! The breathtaking ignorance of this is awesome.

My environment minister is about to bow to environmental ignorance and popularism and ban plastic bags.

As if he had never heard of plastic bottles or a 5c refund on all bottles (My Boy Scout hall was built by re-cycling beer bottles -my Dad built a fair bit of it on his own! :thumbs_up

But now I think I am with Rupert Murdock "You have to give the planet the benefit of the doubt".

 

If any "tipping points' really happen, it is going to get very scary, very quickly.

There is nothing 'out there' that convinces me we are going in the right direction to avoid these Tipping Points..

 

One easy thing farmers (gardeners) can do is sequester carbon (see Terra preta threads). At worse, this helps reduce fertiliser use and fertiliser run-off-pollution.

At best, it slows global warming (or just CO2 increase if you like) while improving soil productivity.

No downside; better than turning off lights for an hour while out at your favourite restaurant; or banning plastic bags for the alternative "Green Plastic Bags":doh:

Link to comment
Share on other sites

While I agree turning off lights for an hour isn't a solution, I do think it is a good thing. It is, at least, somewhat helpful in bringing the issue to the forefront of more people's minds.

Engineerdude, saying 'More than enough research has been done. People currently have nothing to do with global climate' repeatedly doesn't make it so.

Much more research points towards humans contributing to GW than research saying we have absolutely nothing to do with GW. Sure, lots of opinion pieces and op-eds but where is the research?

Did you ever redo your own research which many people here posted possible improvements to? Or did you disagree with the comments about your own experiment?

Link to comment
Share on other sites

I see I'm just echoing Michaleangelica's post, but....

This isn't how our world works. There is no energy trapped or "held" in our atmosphere. The greenhouse effect is like a blanket around our planet - it does not trap energy, it just slows the movement of heat, both coming in and going out. Again, there is no significant energy trapped any place in the atmosphere - changes in air composition just make heat move faster or slower. The only part of the sun's energy that is actually held on earth is that from chemical processes or photosynthesis. The rest of the energy is just moved around and eventually radiated back out to space. The greenhouse effect has no ability to hold any energy.

 

 

Engineerdude,

 

With not enough time, I can only ask that you consider that there is some mechanism by which CO2 affects the balance of heat escaping from our atmosphere into space. You clearly misunderstand the actual mechanism, so without going into all the details, I'd ask that you defer to people who have studied and experimented with this mechanism for many lifetimes worth of work. But....

 

I sure agree with you that there are many immediate, tangible problems which need attention. It is fortuitous that the solution to many of those problems also involves limiting CO2 levels.

 

The three items you mention (...we destroy coral, pollute rivers, erode topsoil...) are "solved" if we reduce CO2 levels: ...to halt acidifying the oceans; and use the sequestered carbon, instead of petrofertilizers, to fertilize our crops--thus avoiding the runoff, helping the rivers--and simultaneously building up topsoil, ala Terra Preta. This is all achieved thru a carbon mitigation strategy that incorporates biochar into more organic agricultural policies and procedures.

 

Regardless of how CO2 affects the climate, could we agree that a program of biosequestration would help the reefs, rivers and topsoils (& possibly help restore harvests in the anoxic coastal dead-zones; reduce our dependence on oil; contribute to a healthier diet and population; focus education more on health and production-- instead of entertainment and consumption; and provide new jobs, careers, and technologies-- helping the economy)?

 

Sorry to get rhetorical with that last parenthetical excursive, but....

 

Rather than spend billions to solve each of these problems individually, maybe we should focus on one, relatively cheap, synergistic strategy as a solution.

 

~ SA

Link to comment
Share on other sites

Another one joins the skeptic crew -

 

American astronaut Dr. Jack Schmitt - the last living man to walk on the moon - is the latest scientist to be added to the roster of more than 70 skeptics who will confront the subject of global warming at the second annual International Conference on Climate Change in New York City March 8-10, 2009.

 

The conference expects to draw 1,000 attendees including private-sector business people, state and federal legislators and officials, policy analysts, media, and students.

 

Schmitt, who earned a PhD from Harvard in geology, resigned in November from......

Astronaut Jack Schmitt Joins Skeptics

 

Its looking to be an interesting and important conference.

Link to comment
Share on other sites

...yes at which point it accelerates the methane molecule that is currently in a gel like state, o the point of releasing a gas, the amount of this gas added to the atmoshere would hold more of the suns energy in the atmoshere...

 

This isn't how our world works. There is no energy trapped or "held" in our atmosphere. The greenhouse effect is like a blanket around our planet - it does not trap energy, it just slows the movement of heat, both coming in and going out. Again, there is no significant energy trapped any place in the atmosphere - changes in air composition just make heat move faster or slower.

 

I believe Belovelife's characterization of "holding more of the sun's energy in the atmosphere" is appropriate.

 

The sun's radiation peaks around the center of the visible spectrum (0.5 μm). As the sun's temperature is much greater than earth's, it radiates at a higher frequency and shorter wavelength than earth’s radiation—as Planck's law says it should.

 

It’s not difficult to calculate the temperature we would expect earth’s surface to be if there were no contribution from greenhouse gas. If we assume that the heat absorbed by planet earth from the sun is equal to the heat radiated from the earth then we can find temperature using Stefan–Boltzmann’s law.

 

The heat absorbed by earth is equal to its albedo times solar irradiance per unit area times the cross-sectional area of absorption.

[math]\mbox{Earth's Heat Absorbed} = (1-a)\pi r^2I_S[/math]

where a is earth’s albedo, r is its average polar and equatorial radius, and [math]I_S[/math] is the radiation flux at our distance from the sun (1360 w/m^2).

 

The heat radiated by earth at a given temperature is given by Stefan–Boltzmann’s law [math]I_E = \sigma T^4[/math] where [math]I_E[/math] is earth’s emitted irradiance and [math]\sigma[/math] is the Stefan–Boltzmann constant (5.67E-8 W/m^2/K^4). So then,

[math]\mbox{Earth's Heat Radiated} = (4 \pi r^2) \sigma T^4[/math]

To solve for temperature we say heat absorbed = heat radiated,

[math](1-a)\pi r^2I_S = (4 \pi r^2) \sigma T^4[/math]

and solve algebraically for T,

[math]T = \left[(1-a) I_S / 4 \sigma \right]^{1/4}[/math]

or,

[math]T = \left[\frac{(1-0.367) (1360 \ W/m^2)}{4 \times (5.67 \times 10^{-8} W/m^2/K^4)}\right]^{1/4}[/math]

[math]T = 248 \ K \mbox{or} \ -25 \ C[/math]

Without any greenhouse effect, earth’s average temperature would be well below freezing around -25° C. This is far below the surface’s actual average temp of approximately 15° C due to greenhouse gasses. This is supported by Historical Overview of Climate Change Science which says (on page 97):

To emit 240 W m–2, a surface would have to have a temperature of around –19°C. This is much colder than the conditions that actually exist at the Earth’s surface (the global mean surface temperature is about 14°C)... The reason the Earth’s surface is this warm is the presence of greenhouse gases, which act as a partial blanket for the longwave radiation coming from the surface. This blanketing is known as the natural greenhouse effect.

They give a slightly higher result of -19° C which I can’t reconcile because they don’t show their work, but the conclusion remains the same.

 

The earth does “hold more of the sun's energy in the atmosphere” due to the greenhouse effect. The average kinetic energy of the surface and lower atmosphere is greater than it would otherwise be exactly because it holds on to the sun's energy.

 

~modest

Link to comment
Share on other sites

... If we assume that the heat absorbed by planet earth from the sun is equal to the heat radiated from the earth then we can find temperature using Stefan–Boltzmann’s law....

~modest

 

curious about where/how the heat from the core figures in to what is radiated from surface? :)

Link to comment
Share on other sites

I believe Belovelife's characterization of "holding more of the sun's energy in the atmosphere" is appropriate.
I agree.

 

Because the Earth’s atmosphere is very large, a small change in its average temperature entails a large change in its total thermal energy. The specific gas constant of dry air is about 287 J/kg/K. Multiplied by the atmosphere’s mass of about [math]5.14 \times 10^{18} \,\mbox{kg}[/math], the energy per degree C temperature is about [math]1.47 \times 10^{21} \,\mbox{J}[/math]. Though small in astronomical terms, this is pretty huge in human terms: about 20 time the world’s annual electrical energy generated and used, or 1/10th the total petroleum and natural gas reserves. It’s even appreciable in terms of the Earths total energy budget: about the same as the total solar energy received in 2.78 hours. And this is only the energy difference for a single degree C change in average temperature.

 

On the other hand, it’s not very sensible to compare the thermal energy of the atmosphere to common power sources, because there’s no practical way to use it directly to do work. Exercises such as the above are mostly useful in keeping a sense of scale and perspective.

 

Sources: Wikipedia articles “gas constant”, “earth’s atmosphere[wiki]”, and “[wiki]orders of magnitude (energy)”.

Link to comment
Share on other sites

curious about where/how the heat from the core figures in to what is radiated from surface? :confused:

 

Good question!

 

The heat flux from the internal heat flow of the earth is approximatly 75 [math]erg \ cm^{-2} \ s^{-1}[/math]. This is given here:

 

Google book source

 

To convert 75 [math]erg \ cm^{-2} \ s^{-1}[/math] to watts per meter squared (since those were the units we were using),

 

[math]\left( \frac{75 \ erg}{s} \right) \times \left( \frac{1.0 \times 10^{-7} \ J}{1 \ erg} \right) \times \left( \frac{1 \ W}{1 J \ s^{-1}} \right) \times \left( \frac{10000 \ cm^2}{1 \ m^2} \right) = 0.075 \ W / m^2[/math]

 

The contribution is then 0.075 [math]W/m^2[/math]. This is verified by this source:

 

Allen's Astrophysical Quantities

 

which gives values of .078 W/m^2 for the ocean and .0565 for land.

 

Thus, the heat contribution available to the lower atmosphere and upper crust from the core is approximately 0.075 W/m^2 compared to the approximately 1360 W/m^2 available from the sun. That's about .005%—it is not significant for the calculation.

 

I hesitate to point at this source, because the first 4 paragraphs are unhelpful and slightly wrong, but it does (at the bottom) the same calculation in the same context as above.

 

~modest

Link to comment
Share on other sites

I have read several posts in this forum commenting on the oceans absorbing excesive CO2.

 

Seems there is a different view :)

 

 

Scientists have issued a new warning about climate change after discovering a sudden and dramatic collapse in the amount of carbon emissions absorbed by the Sea of Japan.

 

The shift has alarmed experts, who blame global warming.

 

Sea absorbing less CO2, scientists discover | Environment | The Guardian

Link to comment
Share on other sites

I have read several posts in this forum commenting on the oceans absorbing excesive CO2.

 

Seems there is a different view :)

 

 

Scientists have issued a new warning about climate change after discovering a sudden and dramatic collapse in the amount of carbon emissions absorbed by the Sea of Japan.

 

The shift has alarmed experts, who blame global warming.

 

Sea absorbing less CO2, scientists discover | Environment | The Guardian

 

The ocean, like all natural systems, has a limited capacity. There is a point where the ocean becomes acidified with carbonic acid and cannot absorb as much CO2.

 

Carbon sink - Wikipedia, the free encyclopedia

Link to comment
Share on other sites

The ocean, like all natural systems, has a limited capacity. There is a point where the ocean becomes acidified with carbonic acid and cannot absorb as much CO2.

 

Thats interesting.... Hmmm, I wonder what happens to excess CO2 trapped under the Artic ice ?

 

Aparently there are some very big undersea volcanoes under the Artic ice cap, and some big bangs of late (has been covered in other threads)

 

Massive amounts of CO2 released - where did it go ? absorbed by the sea water ?

 

(extract)

During the first half of 1999, a long-lived volcanic-spreading event occurred on the ultraslow-spreading Gakkel Ridge in the Arctic Ocean. The seismicity associated with this event was unprecedented in duration and magnitude for a seafloor eruption.

 

Perhaps the closest analogue to the Gakkel event would be the 1783 Laki fissure eruption in Iceland, which produced 14 km3 of lava over about 8 months of seismic activity covering a section 27 km long...

 

http://www.ldeo.columbia.edu/~tolstoy/pdf/Tolstoy_Gakkel.pdf

 

 

(extract)

...data demonstrate that eruptions along the (Gakkel) ridge are larger and more frequent than previously theorized.

 

G. Michael Purdy, director of Lamont-Doherty, said, "A recent eruption on such a slow spreading ridge reaffirms the fact that we live in an era of discovery in ocean sciences. There remains much that is unknown, and even more that is not understood about the sea floor of our own planet

 

News Archive - The Earth Institute at Columbia University

 

And a map - Earthquake record, Artic area

http://www.ngdc.noaa.gov/mgg/avetisov/images/avfig06.gif

 

Map from here - http://www.ngdc.noaa.gov/mgg/avetisov/TOC.htm

Link to comment
Share on other sites

I stuck my nose in the climate science blogosphere and turned up some interesting stuff.

 

First, C Beck from A Few Things Ill Considered shares a gargantuan compilation of climate science news, and apparently one that can be expected weekly:

A Few Things Ill Considered : Another Week of GW News, January 11, 2009

 

 

Also, a paper published in Geophysical Research Letters on Dec 30 2008 entitled "How unusual is the recent series of warm years?" attempts to answer the question asked in the title:

Previous statistical detection methods based partially on climate model simulations indicate that, globally, the observed warming lies very probably outside the natural variations. We use a more simple approach to assess recent warming at different spatial scales without making explicit use of climate simulations. It considers the likelihood that the observed recent clustering of warm record-breaking mean temperatures at global, regional and local scales may occur by chance in a stationary climate. Under two statistical null-hypotheses, autoregressive and long-memory, this probability turns to be very low: for the global records lower than p = 0.001, and even lower for some regional records. The picture for the individual long station records is not as clear, as the number of recent record years is not as large as for the spatially averaged temperatures.

 

 

Good coverage for those of us out of the loop over at Open Mind:

‘Tain’t Likely Open Mind

Every year this century is among the top-10 hottest years on record. In fact the clustering of hottest years is even more lop-sided than that would indicate; by the end of 2006 it was noted that the 13 hottest years on record had all occurred since 1990 (and we’ve added a couple more to that list since then). How unlikely is that?

 

Precisely that question is addressed in “How unusual is the recent series of warm years?” (Zorita et al. 2008, Geophysical Research Letters 35, L24706 doi:10.1029/GL036228). The conclusion can be summed up in a phrase best said with a strong Maine accent: ’tain’t likely.

 

I also stumbled across this: a recent Pew survey indicates that the same crowd known for rejecting the fact of evolution--conservative Republicans -- also doubt that humans have played a part in climate change more than other affiliations.

Why is the Right associated with such anti-scientific sentiments? Is this really the best we can do-- either the Democrats, or the anti-science religious nutters? It didn't seem like much of a choice on election day, and this data further reflects that asymmetric dichotomy.

Link to comment
Share on other sites

Why is the Right associated with such anti-scientific sentiments? Is this really the best we can do-- either the Democrats, or the anti-science religious nutters? It didn't seem like much of a choice on election day, and this data further reflects that asymmetric dichotomy.

 

Well, this atheist Labour voter me, knows i'm winning an AGW debate when somebody trys to bring that sort of a comment to the debate :phones:

Link to comment
Share on other sites

Thats interesting.... Hmmm, I wonder what happens to excess CO2 trapped under the Artic ice ?

 

Aparently there are some very big undersea volcanoes under the Artic ice cap, and some big bangs of late (has been covered in other threads)

 

Massive amounts of CO2 released - where did it go ? absorbed by the sea water ?

 

(extract)

During the first half of 1999, a long-lived volcanic-spreading event occurred on the ultraslow-spreading Gakkel Ridge in the Arctic Ocean. The seismicity associated with this event was unprecedented in duration and magnitude for a seafloor eruption.

 

Perhaps the closest analogue to the Gakkel event would be the 1783 Laki fissure eruption in Iceland, which produced 14 km3 of lava over about 8 months of seismic activity covering a section 27 km long...

 

http://www.ldeo.columbia.edu/~tolstoy/pdf/Tolstoy_Gakkel.pdf

 

 

(extract)

...data demonstrate that eruptions along the (Gakkel) ridge are larger and more frequent than previously theorized.

 

G. Michael Purdy, director of Lamont-Doherty, said, "A recent eruption on such a slow spreading ridge reaffirms the fact that we live in an era of discovery in ocean sciences. There remains much that is unknown, and even more that is not understood about the sea floor of our own planet

 

News Archive - The Earth Institute at Columbia University

 

And a map - Earthquake record, Artic area

http://www.ngdc.noaa.gov/mgg/avetisov/images/avfig06.gif

 

Map from here - Seismic Arctic Earthquakes G.P. Avetisov.

 

If you were trying to make a point, it was lost on me.

Sure, there are natural sources of CO2. There's also human induced CO2.

 

Are you arguing that climate change is occurring regardless of human impact?

Link to comment
Share on other sites

Gentlemen-

 

This is a 20 minute video from 2007 that nicely encapsulates the opposing view. This video is not proprietary.

Discovery Institute

 

 

To my knowledge, there is no contest that CO2 rose over the last century. There is also certainly no contest about whether C02 can act as a greenhouse gas. The issue is whether the increase in CO2 is causal for global warming.

 

In this video, the argument is that warming is better correlated with solar activity over the long term (300 to 1000 years) and that the increase in temperature over the last 100 years is more likely from solar activity than from CO2 increases. It also argues that CO2 increases are generally a result of warming, not a cause (since warm oceans undeniably store less CO2 than cold ones). The recent drop of global temperatures (2008) back to about the 100 year mean supports this position.

 

In this discussion it is nice to avoid references to the "consensus" of scientists. Nothing in science is decided by consensus. Science is not a democracy.

 

Most folks see this sort of presentation and proceed to attempt to discredit the source or the sponsor (as has been done in previous posts). I think this forum deserves to focus on the underlying science, not the perceived biases of the contributors.

Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...