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Global Warming - From Inside the Globe
Bill Kendrick writes "The National Post reports that a team of American and Canadian researchers has found evidence of real global warming: the temperature of the Earth's crust is increasing at a remarkable rate. What's really interesting is that heat absorbed by rocks slowly permeates into the earth. By boring holes in the ground, they can tell how hot the earth was years ago, in a 'reading tree rings' fashion."
Can we all just please realize that humans have been on the earth such a short period of time that we really have no idea how global climate is over a long period of time, so we have no real reference to figure out if humans are the cause of this "global warming"
To some extent that is true, post hoc ergo propter hoc and all that. But if you look at the article more closely, they mention that, and I quote..
"...The warming is most pronounced in northern latitudes, Dr. Beltrami says. On Ellesmere Island and in Alaska, ground temperatures are four to five degrees higher than they were in 1500. The rise is having a significant effect on permafrost, turning some northern areas that were once perpetually frozen into "several metres of muck," he says...."
Surely, this can't all be entirely due to the slow seething disturbances down below. I think humanity, especially post-Industrial Revolution generations have to take some quarter of the blame. It may of course be, that since the earth isn't entirely spherical and the poles are closer to the centre, they tend to get warmer "faster".
There are thousands and thousands of heaters. They are not natural and are causing the planet to warm up. If people would just keep their doors closed with the heater on it would be very beneficial to the animals.
higher than they were in 1500
Well, duh, ever hear of the Little Ice Age? Circa 1400 to 1800, give or take a half century. Prior to that (about 1000 to 1300), temperatures were warmer than they are today. In England farmers raised wine grapes, the Norse had dairy farms in Greenland.
Climate change happens. Ten thousand years ago a good part of North America (and Europe) was under a mile of ice. I suppose humans take the blame for melting that?
Get a grip.
-- Alastair
Heat from 150 years ago is 100 metres below ground? (Depending on the rock). Sort of like tree rings...
"Tree Rings" are the result of bark cycles of the tree. This is *not* the same thing... We're talking about rock that has never seen the light of day... so we're talking about radiation permeating the surface and being stored there like a BATTERY...
What about temperature cycles? Can he "see" the great cold snap of '78?
What about dispersal patterns? Does radiation permeate equally?
And does that mean that the caves that have a constant temperature of ~60 degrees WERE the temperatures thousands of years ago?
What *we* do know... is that its science that makes for good press, politics, and money...
PK
Also from the article:
"Dr. Beltrami and his colleagues from the University of Michigan found that more than half of the land's heat gain over the past 500 years came during the 20th century, and 30% since 1950."
Try to keep an open mind.
Drilling a hole generates heat. Sometimes harder substances generate more heat, sometimes less. While the "heat tree rings" may exist, as seems logical, the act of attempting to observe them corrupts your data.
Using extremely old holes could mitigate this somewhat, but then you have no measure of the geological composition, and therefore thermal properties, of the rock the hole was bored through.
This makes any measurements made of core earth temperature so speculative as to be worthless, except as a very "scientific" expensive way to spread fud. There are quit a few "scientific" methods to measure global warming that are in fact just pseudo scientific pawns in the politically charged arena of environmentalism.
To imagine that we have had no impact on global warming is obviously false. Any argument contrary to what should be painfully obvious to the most casual observer is pure political bullshit.
If voting were effective, it would be illegal by now.
We are not going to destroy the planet by global warming. The earth has endured a great deal of meteorological change and life goes on. The fact is that temperatures are going to change whether we like it or not. I almost think that whether we are making the planet warming by .01 degree is irrelavant because natural changes are probably making it warmer by .5 degrees anyway.
There are better reasons to not cut down forests and to reduce emissions. When people argue global warming, they just pollute the issue and reduce their credibility.
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Dr. Beltrami and his colleagues from the University of Michigan found that more than half of the land's heat gain over the past 500 years came during the 20th century, and 30% since 1950.
So, they believe the rate of warming for 1951-2000 was less than half what is was for 1901-1950. I don't have much basis for an opinion on the meaningfulness of these researchers' results, but I would sure like to know how they explain this apparently levelling off.
*Dig, Dig, Dig*
...
*Dig, Dig, Dig*
...
"Hey Jack, we got two holes dug for ya. Now whatcha want us to do wit'em?"
"Lower the temperature guage into each hole and measure the temperature of the crust at the bottom of each hole. While you do that, I'll calculate the historical dates for each hole based on their depth..."
"Okey dokey boss...well, this here hole's got a readin' of 42 degrees...whatcha make out it's date to be?"
"Okay, according to my calculations, that one is from January of 1849, and the other one is dated to be around July of 1968."
"Okey, well, the udder' hole's got a readin' of 74 degrees."
***Next Day's Newspaper Headlines"***
"Experts Discover Dramatic Global Warming in the Earth's Crust"
Well, since you're apparently too lazy to use Google, I found this one from NASA for you.
In it you'll see that they mentioned the greatest affect on temperature changes seem to have been El Niño.
Anyway, read, learn, enjoy.
Climate change happens. Ten thousand years ago a good part of North America (and Europe) was under a mile of ice. I suppose humans take the blame for melting that?
Oh, you people are so ridiculous, snatching at whatever random fact that appeals to your self-serving opinion. I remember a Christian Science lecturer once told me that the ice age is what allowed the animals from Noah's ark to walk across the ocean and settle on the various continents. I don't think your argument is that bad, but you're still being willfully ignorant.
Scientists believe that a number of factors contribute to large scale climate change:
1. The gradual warming of the sun.
2. The gradual cooling of the earth's core.
3. Large volcanic eruptions and meteor impacts, which pollute the atmosphere with dust.
4. The reflective nature of the polar ice.
5. The population cycles of plants and animals, which change the composition of the atmosphere.
6. The thinning of the ozone layer.
7. The bulldozing of the rainforest.
8. Commercial farming.
9. Atmospheric pollution.
10. Human power consumption.
So the fact that the first 5 elements have caused periodic climate change over the course of Earth's existance does not prove that the industrial revolution is not causing global warming. Furthermore, we have evidence that the effects of mankind are causing climate change to occur much faster than they were previously. On top of this, we have scientific models (based on chemistry and physics) which can accurately predict the warming trend. (We have the examples of the planets Mars and Venus, which provide further test vectors.)
This doesn't mean that there won't be little blips in the data. In fact, a volcanic eruption in the mid 90s caused a 2-3 year disruption in the warming trend (source: the Smithsonian Institute). In the past, large scale climate changes have caused the extinction of large numbers of species. So far, the temperature has always returned back to comfortable levels.
However, the danger of global warming is that several of these factors exist in an unstable equilibrium. As the Earth gets warmer, the polar ice melts. This causes the Earth to reflect less of the sun's energy and more of the ice melts. This results in a 'snowball' effect (to use an inappropriate term). Perhaps in the past, this runaway warming has been quenched by a catastrophic effect like a giant volcanic eruption. Therefore, the equilibrium would be unstable, but chaotic enough to always return to the balance point. There is no guarantee than man-made climate change will have the same effect. Some of the natural factors (e.g. the plant-animal arms race) have a buffering effect, which tends to restore the equilibrium. Man-made factors will get worse as the population increases; they may bias the controlling equations and cause the equilibrium to never be restored.
-a
How to rationalize theft.
Therefore unless if we can know the temperature of the surface of the earth in the past, there is no way of knowing the temperature of the surface of the earth in the past. Am I the only one who thinks this is weird science?
(It's been ten years since I took a PDE course, so parts of this could be slightly off.)
The heat equation looks like this:
du/dt = A * (d/dx)^2 u
where u is temperature, and the partial derivative with respect to time is proportional to the second partial derivative with respect to space (depth). (A is a constant determined by the thermal conductivity of the material.)
To use the heat equation to solve for u(x,t), you need boundary conditions surrounding a two-dimensional domain (space and time). Time here runs from 1500 AD to 2000 AD, and space runs from 0 meters at the surface to 1000 meters at the bottom of the hole. So there are four boundary functions along the extremes of both dimensions:
1. u(0 meters, t)
2. u(1000 meters, t)
3. u(x, 2000 AD)
4. u(x, 1500 AD)
The first one is the function they're trying to get- it's their unknown. The second they have to assume is constant, because there is no way to directly measure it. But since temperature perturbations at the surface of the earth won't have penetrated that deep over the time scale they're looking at, and most of the variability will originate at the surface, this is a fairly safe assumption. The third just requires them to drop a thermometer down the hole, as they have done. The fourth is what you're worrying about, but they don't need it because they have 2. and 3. and can use the heat equation to extrapolate over the rest of the domain.
A problem arises because the left side of the heat equation is a first derivative in time. As time progresses, features in the temperature profile u(x) degrade. (Partial differential equations that have second derivatives on both sides, like the wave equation, don't have this problem.) What you don't want to find, when you measure the temperature down one of these holes, is that the temperature increases uniformly with depth. That means you've waited too long, everything has equilibrated, and both sides of the heat equation are now zero, which prevents you from extrapolating backward. Apparently they must have found some curvature in u(x), or we wouldn't be seeing this article posted.
There are other complications. The thermal conductivity constant won't be uniform with depth, for example. What that means is they need computers to solve for u(x,t) numerically. Partial differential equations can almost never be solved symbolically anyway, so this isn't much of an issue.
Can you provide a link? Last I checked we didn't even have a model that successfully modeled the increase at the beginning of the 20th century. And no model that takes into account the affect of solar variations and the affects of (ahem) clouds.
If modeling is really as good as you've suggested, I've apparently missed something and I'd very much like to see that model and educate myself.
I am devoting my life to the continuation of global warming. I promise I will not rest until the North/East (my home) has Florida like weather conditions year round.
I wonder how many "sciantists" you could get to sign a "anti-evolution" petition. A lot, probably.
The number of "sciantists" who sign an online petition isn't proof of anything.
autopr0n is like, down and stuff.
Duh ! What is this silly nonsense? Do you think heat is some kind of liquid that is affected by gravity and slowly soaks down through the rocks? Heat flows in all directions.
I don't think you understand something. Nowhere in the article did it say heat was "affected by gravity". Heat does show limited properties of signal propagation, because it flows at a finite rate along a gradient of decreasing temperature and is always conserved. (Meaning, because of the First and Second Laws of Thermodynamics.)
And measuring temperature alone provides little useful information, you also need to know the thermal conductivity and specific heat of the medium(rocks), which is highly non-uniform.
This just requires extra data on rock composition, which is well known and easily accounted for in any computational heat equation model.
Old boreholes? Give me a break. The air convection in the hole will effect the measured temperature.
Air convection is unlikely to be much of a problem at all. Air is a good insulator and a borehole of air has low thermal mass. Water convection is a much larger problem. This is from their web site, explaining how they get rid of environmental interference:
Temperature perturbations in boreholes are produced by several processes. For climate reconstruction it is important to distinguish between a changing temperature through time at the Earth?s surface and other sources of temperature perturbations.
Geologic conditions and processes, other than climate change, that produce curvature in temperature-depth profiles include the following: (1) systematic variation of thermal conductivity with depth, (2) radioactive heat generation in rocks, (3) topography, (4) lateral variation of surface temperature caused by surface orientation, changing vegetation, or variable snow cover, (5) uplift and erosion or subsidence and burial at the site, and (6) vertical percolation of groundwater.
Several approaches are taken to isolate and correct for temperature anomalies from these sources. Available topographic and geological information available at each borehole site allows one to compute the magnitude and expected shape of temperature perturbations from each source. Sites can be discarded if the geologic disturbances are too large, otherwise corrections can be made. It is also possible to combine or stack temperature anomalies from several nearby drillholes. As geologic, topographic, and hydrologic conditions at each hole are unlikely to be identical, spurious temperature anomalies are likely to cancel. If each hole has experienced a similar climatic thermal signal, the climatically induced temperature anomalies will constructively interfere in the stacked temperature profiles.
There is one very efficient method of isolating climate change effects in borehole temperatures but the method requires patience. All of the non-climate sources of temperature anomalies are steady state, or quasi steady state relative to the time scale of climate change. Thus curvature in temperature profiles from these sources is stationary in time. By measuring and remeasuring borehole temperatures after an appropriate time lapse, changes in temperature with time can safely be ascribed to climatic sources. Several monitoring experiments are in progress. With present technology available to measure temperatures in boreholes to better than 10 mK accuracy, the repeat time to isolate climate-change signals is about 5 years.
So it appears they have thought of some of these things.
I for one don't believe any such thermal signal more than a few years old can exceed the noise threshold.
It's clear you haven't read the paper, but I guess I'll take your word for it. You should know.
Ok, but a model has to work in all cases to be valid. As you can see they were pretty excited because in this one particular case they got it right. I.e., they were surprised because most of the time their models don't work.
The question is whether that model worked for climate change before and after that 2-year period that it supposedly got it right.
If I flip a coin enough times I'll eventually predict global climate change, too.
In any case, whether or not, they can model the Earth as a whole, I don't see how anyone can deny that they have the ability to model the effects of each factor individually, and those models should lead you to the same conclusions.
That's not true, either. They might be able to approximate affects of some factors, but until they can approximate everything that plays a factor then it is truly impossible to say how much a given factor will affect the whole.
I'm not saying they should stop trying to model. Just that right now the models don't tell us anything and they need to keep working on it.
If you talk to Europeans, they accept that the Earth is warming up and think that something must be done to prevent it from messing up the balance of nature.
If you talk to people from the USA, they come up with who knows what explanations about why the Earth is not warming up. Why is it so? Do they teach you at school that the Earth may not warm up and thus it is perfectly safe to pump more CO2 and other greenhouse gasses to the atmosphere?
There still is an ozone hole. The Earth is warming up. Okay, the ozone hole is not so large as it was a few years ago, but this was because ozone-layer eating gasses were banned.
Think about it, if everyone had thought "what a bunch of hippie communist propaganda, ozone-schmozone, ha" things would be different now. In that scenario you had better not go to Southern Australia for a vacation.
So, please explain what drives especially people from the US to close their eyes from the facts and cite corporate spin doctors who offer "proof" about why the planet is NOT warming and hence it is safe NOT to invest in expensive modifications of manufacturing plants or environmentally friendly technology.
I would love to create stockholder value, but I'm constipated right now.
Get over yourself. There isn't any shortage of ideological blindness on "your side" of this issue either.
Ah, but I don't personally benefit from global warming being true. Actually, I suffer from it. I would LOVE global warming to be a myth; I live in a coastal city, and don't really WANT it to be under water in a few decades.
And I didn't have an opinion one way or the other until I went to college and started taking courses in climatology/metereology. Despite the right-wing FUD, climate is monitored very closely, and there is ample evidence that many climatic factors have anthropogenic sources.