Lois & Clark Forums Forums General Discussion Off Topic Global Warming (or not)

Um, you did notice the winking smiley after my comment? That's because I was being ironic.

I think you got something confused. It's both carbon causing 'global warming' (if you believe in it) and the cooling after the eruption of great volcanoes. But the first is carbon dioxide, and the second is made up of larger particles you'd refer to as ashes. These ashes build huge clouds, preventing sunlight from reaching the ground. And without sunlight, it gets darn cold down here.

Since we already mentioned volcanoes, we should talk about the so-called super volcanoes as well.

There are several known super volcanoes around the world. One of them, Lake Toba in Indonesia, erupted about 75,000 years ago, spewing forth about 2,800 cubic kilometers of ashes (Compare: Krakatoa: 25 km³; Mount St. Helens (last eruption): ~1.2 km³) and causing the so-called Millenial Ice Age.

Here is a list of other supervolcanoes and information on their eruptions:
Lake Taupo, New Zealand, erupted 26,500 years ago; ejecta volume: 1,170 km³

Yellowstone Caldera, Wyoming, erupted

• 2.2 million years ago; ejecta volume: ~2,500 km³
• 1.3 million years ago; ejecta volume: ???
• 640,000 years ago; ejecta volume: 1,000 km³

Valles Caldera, New Mexico, erupted

• 1.6 million years ago
• 1.2 million years ago; ejecta volume: >2400 km³ (each? together? Couldn't make sense of my source)

Long Valley, California, erupted 760,000 years ago; ejecca volume: 2,400 - 3,600 km³

La Garita Caldera, Colorado, erupted 27.8 million years ago; ejecta volume: ~5,000 km³

Oh, and some of them, namely the Yellowstone Caldera, Lake Taupo and Long Valley are still *very* active. Plus Aira, Japan which doesn't have a claim to such a 'mega-colossal' eruption - yet.

Apart from that, I have to agree with Paul: We can do nothing to preserve our environment and find out it would have been necessary, or we can do something and find out it wouldn't have been necessary. Personally, I prefer the latter.

Another thought: People interested in this topic should read Michael Crichton's 'State of Fear'. Really interesting, if a bit one-sided.

As to what we can "know" about global warming, remember that science isn't about knowing the full and perfect truth. Science is about postulating hypotheses - such as, for example, "the release of greenhouse gases into the atmosphere by the burning of fossil fuels contributes to climate change" - and then you must do your very best to test those hypotheses. For example, it is a well-known and easily established fact that a number of greenhouse gases and pollutants really are being released into the atmosphere. The atmosphere of the Earth today is different than it was, say, three hundred years ago. It is in fact different than it was one hundred years ago, too. It is also a fact that the climate of the Earth has grown steadily warmer, certainly during the last thirty years.

However, how can we know that there is a connection between these two facts? How do we know that there is a causal relationship between them? How do we know that the warmer climate of the Earth is wholly or partly casued by human activities?

In fact, it seems almost certain that the existent warming isn't caused exclusively by humans. Variations in the energy output of the Sun most certainly contribute. But if scientist believe that humans contribute to the global warming, what reasons do they have for this view?

Well, there is such a fact as the scientific understanding of what a greenhouse gas is in the first place. It is a gas whose physical and chemical properties causes it to trap some of the heat which has entered it.

By looking at our own Solar system, astronomers can witness the effects of greenhouse gases. Venus, the planet which is in many respects the one most like the Earth, has an incredibly thick atmosphere mostly made up of carbon dioxide. Scientists calculate that if Venus had an atmosphere with the same amount of greenhouse gases as the Earth, its temperature would be around 90 degrees Celsius, not enough to boil water at sea level on the Earth. However, the temperature of Venus is over 400 degrees Celsius, hot enough to melt lead, and more than four times hotter than it "ought" to be. Mars, on the other hand, has a very, very thin atmosphere, which doesn't contain huge amounts of greenhouse gases, even though it's true that the atmosphere of Mars is made up mostly of carbon dioxide. Many scientist believe that Mars was considerably warmer in the past, since there are many dry riverbeds on the red planet, bearing witness to the presence of abundant liquid water on Mars in the past. Many astronomers therefore believe that Mars' present cold climate is caused at least partly by the loss of greenhouse gases. (It should be noted, too, that some of the most gung-ho and optimistic astronomers talk about "terraforming" Mars, that is, making it Earthlike. This will require a rather drastic raising of global temperatures on Mars, but the optimists think they can achieve this by releasing a lot of greenhouse gases in the Martian atmosphere.)

We may also note that the present rise of temperatures on the Earth appears to be unusually fast. And it is happening at the same time as humanity is using up fossil fuels and releasing carbon dioxide into the atmosphere at an unprecedented rate.

In short, the amount of greenhouse gases in the atmosphere of a planet appears to affect the planet's overall temperature. Most scientists therefore believe that humanity's present fossil fuel behaviour contributes to global warming. There is, however, no such thing as absolute scientific proof of this. However, if we find the scientists' arguments reasonable, it might be a good idea to reduce our appetite for fossil fuels.

Ann

I agree with most everything you said. We have no way of knowing how much of our contributions have to do with warming the planet. We only know that it is warming. That being said, I also agree with Paul that reducing our appetite for fossil fuels can only be a good thing, if for no other reason than it is a finite resource. I would much prefer to base our energy needs on renewable resources, such as corn, nuclear (where's my Mr. Fusion!), or other sources, but that transition needs to be done smoothly without destroying our way of life as so many of the global warming alarmists want us to do. Kyoto is their effort to essentially destroy America's economy.

I do disagree about the "most scientists". I saw a study a few months back that claimed most true environmental scientists (not politicians or scientists in other fields or others who claim to be like the Center for Science and the Public Interest, who serve neither science nor the public interest) DOUBT significant human effects on global warming. There was even a paper written a few years ago disputing the alarmists, signed by 17,000 environmental scientists. Don't underestimate the effect of the media on making us believe that there is little to no dispute. According to most of the media, global warming is fact and all scientists believe it.

As I said, read 'State of Fear'! It's really interesting.

I see your point, Alcyone. But we still need to be cautious. A hundred years ago, a consensus of scientists were convinced that the universe had no beginning and that eugenics were moral. There were respected and intelligent people who defended those positions.

And you know, scientists are people, too. They've got biases and opinions just like the rest of us. So it's possible (not inevitable, but possible) for those to influence their conclusions.

Thanks for the data, Olympe. Interesting...

Well, the trouble with that is opportunity costs. (It's Saturday night. Your parents want you to do something with them. Your friends want you to do something else with them. You can't be in two places at one time, so you have to choose. Well, you weigh the pros and cons, and then decide which you'd rather do -- but my point is, in choosing one to do, you're choosing another *not* to do, and there are consequences to that.)

It's all very well to talk about "doing something" but we have to look at the costs as well as the benefits. One of the things that bothers me is that "environmentalists" are advocating policies that keep developing countries from developing. There's a reason we use fossil fuels -- they're very cost-effective. Banning (or drastically restricting) them would economically cripple the developed world and devastate the poor countries. Is it moral to harm billions of people now, just in case it makes a difference, later?

PJ
...speaking of Mars, there's global warming there, too. Must be all our polluting space craft ruining the neighborhood...

That was my point exactly, so that "but" sounds to me like a misreading of my post. I'm not saying one thing or another about global warming. I'm basically saying that total objectivity or a science that lacks politics are both naive assumptions that are there so people can sleep better at night.

Any defense of something on the basis that it is an "fact" draws the eyebrow of skepticism from me, either way.

I know that for a "fact" , so once more I'm hoping you're not directing it at me. That's why I mentioned awards and tenure, and also there's the whole issue of funding. Whoever funds you be it government or the corporate sector demands results. I live with a scientist, trust me, not all the data you get is as is. Everything in life is drenched with politics.

Other than that abstract thought, I really don't want to jump into this debate in full. I'm aware that my own politics shine enough as it is and that really, I'm not about to get my opinion changed or change someone else's.

Enjoy guys,
alcyone

Indeed, Pam, there is global warming on Mars. And it isn't caused by our space craft, no. The overwhelmingly likely explanation is variations in the activity of the Sun. For all of this, Mars is still very, very cold.

I am one of those who firmly believe in the majority view of scientists that the Earth is about four and a half billion years old (give or take a couple of hundred million years). I also believe that life on Earth is around three billion years old (this, too, is a consensus belief among scientists). Furthermore, I believe that life has kept on existing here more or less continuously since it first appeared here. If that is true, then life has existed continuously on the Earth for three billion years.

Now, practically all scientists believe that all life on Earth requires liquid water. People, do you realize what that means? If life has existed on the Earth continuously for three billion years, and this life has continuously required liquid water, that means that the temperature on the Earth has varied by less than a hundred degrees Celsius for three billion years! It has varied by less than the temperature span between which water freezes and water boils!

Doesn't this sound incredible to you? Okay. Then think of this. Astronomers study millions of stars in the sky, and they are particularly interested in stars in clusters. The overall properties of a cluster give a very good indication of that cluster's age. By studying many clusters of different ages, astronomers have reached a rather firm conclusion that stars steadily grow brighter as they grow older (up until a certain point where they die, of course). The fact that the stars grow brighter shows that they put out steadily more energy into space.

Now, because of this observation that stars grow brighter as they age, astronomers have concluded that the Sun is 20-30% brighter now than it was when life first appeared on the Earth, three billion years ago. In other words, the Sun puts out 20-30% more energy now than it did when life first appeared on the Earth. For all of that, the temperature of the Earth has remained virtually unchanged for these three billion years!!!

To make you see the situation more clearly, let's talk about the temperature of the Earth in degrees Kelvin, since the Kelvin temperature scale starts at absolute zero (that is, at the coldest possible temperature in the universe). Now, ice melts (or water freezes, if you want) at 273 degrees Kelvin. When life first appeared on the Earth, the overall temperature of the Earth can't have been much lower than that. During the twentieth century, when the Sun had grown 20-30% brighter, the overall temperature of the Earth was about 288 degrees Kelvin (15 degrees Celsius). This means that while the Sun grew 20-30% brighter, the temperature of the Earth rose by, at most, a little more than 5%. And that is assuming that the overall temperature of the Earth really was very close to the freezing point of water, 273 degrees Kelvin, three billion years ago. If the temperature back then was higher, the temperature increase since then has been even smaller.

So, people, this appears to be the situation. The temperature of the Earth has remained absolutely incredibly constant for three billion years. There are various reasons for this, the most important one being that when the Earth first formed, it was actually molten. It has slowly cooled ever since it formed. And for three billion years, the gradual cooling of the Earth has been almost perfectly balanced by the increased energy output of the Sun.

A colleague of mine, a man with relatively conservative political views, was recently quite shaken by a TV program he had seen about global warming. In this program, a scientist claimed that during the latest ice age, Earth had apparently only been two degrees colder than it is now. Two degrees! And this was enough to plunge the Earth into an ice age! According to other scientists in the same program, if the current global warming trend continues unchecked for a hundred years, the Earth will become four degrees warmer than it is now. Four degrees! If a temperature drop of two degrees could plunge the Earth into an ice age, what will a temperature increase of four degrees do to this Earth?

My point is that the Earth has been dancing on a knife-edge of a temperature balance for three billion years. Sooner or later we are going to fall down from this wonderful thin line of perfection. Unfortunately we can't look into the future, and we don't know all the facts about the Earth's total energy and temperature budget. But personally, I believe in two things. Greenhouse gases in the atmosphere increase the temperature of a planet. And the Sun is growing progressively brighter, putting out more and more energy into space. The gradual changing of the Sun is enough to guarantee that we are going to see global warming in the future. If we burn fossil fuels at an unprecedented rate and give the Earth an entirely new source of greenhouse gases - that which is coming out of our man-made chimneys and exhaust pipes - then the global warming which is inevitable in the long run anyway could conceivably come that much sooner.

Ann

Good thing God is there to keep things regulated, isn't it?

I prefer to think of it as a good thing God set up such an incredible self-regulating system More or less constant temperature for 3 billion years is no small feat of engineering. However, that's a whole 'nother discussion, and I'd really rather not do it in here.

PJ

OH MY GOD, WE'RE ALL GOING TO DIE!

Notice I don't say when.

I've been ignoring the news on this for the most part. I agree with many of the points here (look! a consensus!). Goodness only knows what effect we have on the overall temperature, but we are on an unstable rock. The molten core continues to burn, the sun will fluctuate, and California may fall into the Pacific. We're just little ants trying to find our way back to our hills. (forgive my prose, it's slightly past my bedtime)

One thing I do agree with is that we're burning up our natural resources faster than we can replenish them. I'm just hoping my little bit of recycling is doing its part to help out. And I hope we can find an alternative to some of our finite resources soon. (I want my Mr. Fusion, too! And my flying car, dang it!)

At the same time, it would be stupid not to learn from our past mistakes. Regardless of whether global warming is the fault of us humans or not, toxic emissions harm our planet and us in other ways: acid rain, diseases etc. So focusing on renewable energy sources even in developing countries seems more "moral" to me, because it takes into consideration sustainability--after all, fossil fuels are running out.

Not planning ahead is stupid, just like insisting on "staying the course" when it turns out you've screwed up .

Just today, there was an article posted on a site called Spaceflightnow about climate change, where the Earth is compared with Venus and Mars. According to that article, Venus and Mars were originally fairly Earthlike, but later on they suffered climate catastrophes.

The article stresses that Venus has suffered a runaway greenhouse effect. This happened after its atmosphere slowly changed until it reached a point of no return. Since there are no people on Venus polluting its atmosphere, most of the atmospheric change of our sister planet was driven by the steady brightening of the Sun. (The rest of the atmospheric change of Venus may have been caused by heavy volcanism on this planet.)

The article quotes David Grinspoon, one of the scientists working on the Venus Express mission, who says that the changing atmosphere of the Earth, too, may reach a point of no return, after which there will be a runaway greenhouse effect on our planet. Scientists do not yet know how close we are to such a point of no return.

Here is a link to the article:
Climate Catastrophes in the Solar System

Ann

OMG! THOSE SELFISH PEOPLE ON VENUS, DESTROYING THEIR PLANET! What was wrong with them, didn't they realize the consequences of their next hundred years????

Oh yeah, there WERE NO people on Venus. It just changed...all by itself. Because of the sun I bet.

Seriously, there is NOTHING, not a damn thing we can do to change the what is going to happen to this planet. When human beings can get over themselves and figure that we are all in God's hands, then we can stop wasting our time worrying about stupid stuff.

One of the big things this "global warming" farce has become is a money venture, and that's all that's driving it right now. There's lots of cash to be made of those "carbon offsets" and it's not gonna be believable until we see the money stop flowing.

You know, I had this long and rather sarcastic response all typed out, but then I figured why bother. If you'll excuse me, I'll just go bash my head against a wall, now.

You are right that there is nothing we can do to stop the Sun from eventually frying the Earth. However, we probably can do something to prevent the hastening of the demise of life on Earth. Earth can really be compared with a living organism. There is nothing you can do to prevent a living organism from dying eventually, but you don't need to treat it badly and make it develop bad habits so that it dies sooner.

Those of you who believe that we don't have to take care of the Earth because God will do it for us might want to consider these words from Genesis:

From a cosmic perspective, the Earth is truly a garden of Eden. The catastrophic failures of planets like Venus and Mars prove how difficult it is to come up with a perfect planet like the Earth. So if we think of the Earth as the garden of Eden, which is not unreasonable, then maybe we should also think that God put us here because he wanted us to keep and preserve the Eden he has given us. At least, when we knowingly change the composition of the Earth's atmosphere, we probably shouldn't tell ourselves that God will magically remove the extra greenhouses gases that we dump in the air.



Ann

Sorry TOC, but your quote doesn't hold up.

''Sorry. No results found for "The LORD God took the man and put him in the garden of Eden to till it and keep it. " in Keyword Search.''

Got that on Bible Gateway. 'Course I only checked the New International Version, the New King James Version and the New American Standard version, so I would be curious to know where you got that one, 'specially since I know Adam didn't have any tilling to do until after he and Eve tried to make themselves equal to God.

I also got this:
Love the LORD your God with all your heart and with all your soul and with all your strength.
Deuteronomy 6:4-6

See the problem with people so focused on earth worship, they forget where they come from, they forget where their attention should be aimed.

With all the waste spent on the farce that is global warming, wouldn't be surprised at all to see the sun come rushin' at us one day, especially during a "burning man" festival, because there's one thing I've learned in my 37 years is that God's got an ironical sense o' humor. (Ya'll 'scuse my Firefly speak, been marathoning all morning)

That's all I got to say on this. Ya'll enjoy your discussion

I quoted my own English-language Bible, which is The Holy Bible, The New Revised Standard Version with Apocrypha, Black Letter Edition, Thomas Nelson Publishers, Nashville, copyright 1989 by the Division of Christian Education of the National Council of the Churches of Christ in the United States of America.

As for chapter and verse, the quote is Genesis 2:15.

Ann

Oh, National Council of Churches? That explains it. They haven't been Christian for a long time...

PJ

Hmm. My version (KJ version) says "dress it and keep it." And now I canNOT get a picture of the earth in a frilly dress out of my head.