not questioning the reality of climate change

but the cause

seems to me that the Earth's climate has been forever changing .... but now we are capable of measuring & worrying ... whereas the tyranosaurus had no way to measure the rising temperatures & frequency of hurricaines

I am not convinced this is due to US

but is perhaps a part of the natural cycle

and since "2" lived through the last ice age ... I thought I'd ask HIM

<img src="/ubbt/images/graemlins/laugh.gif" alt="" /> Pep

Though I don't really know, I admit that I am skeptical of anything that Gore is purporting.

It would be nice to be able trust sources to be objective and not be swayed by political leanings.

We are all human and come about our own leanings and beliefs through our own life experiences, observations, exposure, things we expose ourselves to, what we choose to read, and our own research.

Hi Pep,

I understand. Yes, the climate has changed a lot in the past.

What is different this time around is the rate of change. In the past, change occurred over a few thousand or tens of thousands of years. That allowed some time for natural selection to occur. There were extinctions, but many species survived, migrated, adapted in some way. This time, change has occurred over 150 years. It is an exponential relationship, ie the rate of change is only increasing. So most of the change has happened over the last 10 years.

There is a very strong regression relationship between conc of CO2 in the atmosphere and the rate of av world temp increase.

There is a very strong regression relationship between conc of CO2 in the atmosphere and increasing fossil fuel use.

You decide.

Smur, you said:

"About solutions? Renewable energy development. Sensible energy pricing stategies to discourage waste. Nuclear power. None of it is beyond any developed country, and none of it requires huge lifestyle changes. Look at Sweden. "

All wonderful ideas, I say. Tell it to our VP next time he has a Strategic Energy Policy Summit. Oh, I forgot, folks with fresh ideas need not apply. Get that sunscreen out....

Dear fellow MB'ers.


The US carry the main burden in the world wide fight for freedom and democracy. I would then really have expected that this level of responsibility was also manifested in a concern for the environment. To me both these struggles are for the same cause: To make the world a place to live in for our children and their children.


Edited to shorten. The first section said best what I wanted to say.

Announcing that my next home will be almost completely energy independent - wind and solar (with a little diesel if I want to run the AC and propane/charcoal for cooking). And it'll be immune to rising ocean levels. <img src="/ubbt/images/graemlins/grin.gif" alt="" />

WAT
-------------
Before you know it they'll start claiming that people are made of atoms - just like rocks and stuff.

I've always liked the idea of being self-sufficient. We originally started out 30 yrs ago with a piece of land in Maine, intending to build a post and beam, energy efficient home. We took the Shelter Institute Course in preparation.

Plans changed and we moved to Florida (it was supposed to be a temporary move) and ended up raising our kids in a small town neighborhood...not 'back to the land' as I had intended.

I don't like to be so dependent on fuel and electricity. Where we live you, it is very difficult to go anywhere without a motor vehicle. It can get pretty miserable without A/C too.

I won't have one - at least not one with wheels.

<img src="/ubbt/images/graemlins/grin.gif" alt="" /> <img src="/ubbt/images/graemlins/grin.gif" alt="" />
WAT

Sailing, sailing, over the ocean blue.... <img src="/ubbt/images/graemlins/cool.gif" alt="" />

I'm very surprised that in 2006 anyone is questioning the reality of climate change.

The reason some of us question is because there is so much mis information. Including the statement below which I don't believe is the truth.

In 1995, 200 scientists, including all the world's top climate scientists, wrote an open letter to heads of government to say there was overwhelming evidence of climate change having already occurred, and that something needed to be done and fast.

To say "ALL" the world top scientists is not true. Some of the words top sicentists disagree - and Graycloud noted one of them in one of his posts above.

This was unprecedented. Getting 200 free-thinking, ambitious and opinionated scientists to agree is next to impossible.

As noted, there are some who disagree - You are only looking at one side of this.

Since then, the evidence has only become stronger.

The evidence is overwhelming that there is climate change, but not what caused it. The the ice core studies show there have been other changes more drastic than this when no green house gases were present.

Why would every head of government in developed nations with the exception of the US and Aust agree to the Kyoto protocol, despite the fact that it will cost a lot of money, unless there is incontrovertible evidence?

You got me on that one.

I believe Graycloud when HE says it is man caused, because I trust him - but so many people use untrue absolutes like you did to try prove their point of view when they should be using the truth instead. My opintion is that this is part of the problem and is why many don't believe.

Please note I agree with you about Global Warming, but not with some of the ways you reach the conclusion.

SS

We can identify the natural cycles that might have an impact on climate. Actually, rather than separating "natural" and "not natural", it makes more sense to just identify "forcings" - phenomena that can influence climate. Everyone studying climate agrees that they exist.

They are:

* Changes in the amount of solar radiation arriving at the earth's atmosphere and surface and not being reflected and returned to space.

* Changes in atmospheric greenhouse gas concentrations.

The Earth's climate is responsive to any of those forcings. The question is, for any forcing, how responsive? On the grand scale, there are two potential responses to any climate forcing:

1. A change in the amount of radiation reflected into space by snow, ice, clouds, and the surface (this is called the albedo).

2. A change in the amount of energy absorbed and sent back toward the surface by water vapor, methane, carbon dioxide, and other greenhouse gases.

Notice that the responses are basically the same as the forcings. That's why they're called "feedbacks".

They can work in two directions.

If you increase CO2, the planet warms by some amount. If the warming is significant, the atmosphere begins to hold more water vapor, which is itself a greenhouse gas that enhances the warming. That's a positive feedback.

Another one: say you increase CO2 enough to warm the Earth so that the sea ice over the Arctic Ocean melts. Prevailing winds passing over the arctic and then flowing onto Alaska's North Slope now have a greater ability to collect water from the surface of the Arctic, and massive snowstorms begin to cover the North Slope in snow, increasing the Earth's albedo slightly and contributing to a cooling effect. That's a negative feedback.

So-called catastrophic climate change, such as the onset of an ice age, is normally thought to be a series or combination of positive feedbacks dominating the climate's response to a forcing.

There is no doubt that a change in the atmospheric concentration of any greenhouse gas is a forcing mechanism for climate.

There is no doubt that the 30% increase in atmospheric CO2 since 1850 was almost entirely put there by the burning of fossil fuels

Given those two statements, which no serious scientist would dispute, I guess the biggest question I'd have if I was more confused would be simple:

Are significant changes in CO2 an important mechanism for climate forcing;

i.e.

Is the climate system sensitive to changes in CO2?

That's really the million dollar question.

To find out, climatologists attempt to reconstruct history using data and computer models.

Some of the data we have on the climate's sensitivity to forcings, and on the magnitudes of the various forcing mechanisms, have only been available for a decade or two. Some of have been collected for the last 50 years. Some for 100, some for 200, some for 400. Some information can be gathered by examining isotopes in various mineral, ice, and fossil deposits and inferring the way the system evolved over geologic time.

Generally, the farther back you go, the less reliable the data become.

Therefore, somebody saying "During the Late Ordovician era 450 million years ago, the atmosphere had 12 times the CO2 of the present day atmosphere and it was one of the absolute coldest periods in the Earth's history" is not a terribly useful statement, since that characterization of the ancient Earth is very, very, very uncertain. Certainly too uncertain to used as compelling evidence to by itself either support or dispute the theory that the Earth's climate is sensitive to changes in CO2.

That would be like looking for a correlation between two variables by plotting them as a series of points on a graph, seeing one point with a huge error bar that doesn't fit the correllation suggested by the other data, and saying, "There is clearly no relationship between these two variables because of that one point with the giant error bar that doesn't fall on the curve we're trying to fit."

Sorry, that might be a little too sciencey for some people.

For me here are the most compelling reasons I'm convinced the climate is sensitive to changes in CO2.

Fundamentally speaking... if you do the most basic energy balance calculations for the earth, CO2 matters. If you take it away, the planet's mean temperature is 5-10 Celsius degrees cooler. By "common sense", you'd expect that increasing it by 30% will have a significant effect.

When the climate of the 20th century is reconstructed using the same models that are used to predict future climate, and the best forcing data available are included, the 20th century climate variability is reproduced very accurately (including the cooling from the 1940s-1970s). However, the models can't reproduce it without realistic CO2 forcing.

When the climate of the last ice age is modeled using the same model sensitivities, and the best data available, most models can only reproduce the estimated temperatures from that period by including the far lower concentration of CO2 estimated to have been present at that time. Without the lower CO2, they can't get it to be cold enough.

Inconsistencies in the geologic record such as the "Late Ordovician Mismatch" are important issues to resolve, no doubt.

Basically, climate models are quite uncertain. But like the simple energy balance calculation for Earth, they have a significant sensitivity to CO2. Without realistic CO2, they just don't perform well.

A researcher like "noted global warming skeptic" Richard Lindzen now makes his living by constructing theories to support the hypothesis that the climate is not sensitive to CO2. Those efforts are valuable, no doubt. So far, they have supported the notion that the climate is sensitive to CO2.

GC

I might start holding my breath more often to do my part

<img src="/ubbt/images/graemlins/smile.gif" alt="" />

It will take me some time to read & digest your post G

thanks very much

I will be back later with questions

Pep <img src="/ubbt/images/graemlins/smile.gif" alt="" />

Holding your breath? Don't bother.

The amount of carbon on earth doesn't really change. It's stored in four reservoirs:

1. The air, mostly as CO2
2. The water, as dissolved CO2
3. Biomass (current and former plants and animals)
4. The earth's crust

There are significant fluxes of carbon between the first three all the time, and the balance among them all is called the carbon cycle. Sarge breathing is part of that balance.

However, the use of fossil fuels takes carbon from #4 and sends it to #1. There is no significant flux of carbon into #4, so the extraction and combustion of fossil fuels (and to a far lesser degree volcanic activity) just increases the overall budget of carbon that gets exchanged between #1-3.

The "Is CO2 a pollutant?" debate is a red herring. Of course CO2 is natural. But CO2 from fossil fuels is "new" CO2 for #1-3, and in that sense, it's disruptive to the carbon cycle.

GC

Again, this is getting a little out of my range, but it's interesting 2 contemplate.

One of the potential unknowns at this point is how fast gc's #3 responds 2 an increase in atmospheric CO2. Are forests growing faster than they did in 1850? So much of being able 2 answer that kind of 2uestion centers around our "resolution" of the evidence for it. Tree rings, for example, might be expected 2 be spaced wider during rapid growth periods. But there are so many other factors affecting tree ring growth that I doubt it's easy 2 separate them with any certainty.

Sea level change is another one. Tidal variations in sea level vary considerably from place 2 place depending on things like geographic location, orientation of the coastline, bottom profile topography. And measurements of average sea level globally have only been monitored for decades at most, though some locations may date back centuries. And those measurements must also take things like tectonism in2 consideration - the coastline around Camp Pendleton, for instance, has risen hundreds of feet in the last several hundred thousand years. (edited 2 clarify: the land has risen relative 2 sea level, so there are coastal terraces and sea cliffs hundreds of feet above modern sea level - I-5 is on a big one).

Venus, Earth, and Mars are all thought 2 have started life out pretty similar - with massive CO2/steam atmospheres during and after planetary accretion. Venus and Earth are pretty much identical in size and initial volatile inventory, and even their position in the solar system is pretty similar (Venus is only about 25 million miles closer 2 the sun than Earth), and yet they're climates are radically different. Venus' 90 bar atmosphere is almost entirely CO2, with sulfuric acid clouds and other stuff in trace amounts. Earth's similar CO2 budget is largely locked up in carbonate rocks - the whole state of Florida is water-soluble, for example (witness all the sinkholes they get there). As the three planets cooled from accretion, water condensed in2 liquid on Earth and Mars, allowing carbonates 2 form, but tempera2res on Venus may never have fallen enough for water 2 condense, such that water vapor and CO2 - both greenhouse gases - drove the global tempera2res ever higher, water dissociated in the stratosphere, and the solar wind - unimpeded by Venus' lack of a magnetic field - literally eroded the upper atmosphere of Venus so that 2day there is less than a meter equivalent of water in its atmosphere if it could condense and be spread evenly over the planet.

Venus is indeed the most he11-like planet in the inner solar system.

-ol' 2long

This board never ceases to amaze me. I mean in a GOOD way. It may surprise you all to know that in the rest of the world Amercians are sometimes perceived as being "once over lightly" in their views of the world (which is not just the US) and the world's problems.

You guys are just AMAZING. The considered arguments, the listening to other people's opinions, the out and out KNOWLEDGE is just awe inspiring.

You are all THE BEST <img src="/ubbt/images/graemlins/grin.gif" alt="" />

I love it. So when IB (my WH) gives me grief I can tell him to go to Venus??? <img src="/ubbt/images/graemlins/grin.gif" alt="" />

Wouldn't Uranus be more appropriate? <img src="/ubbt/images/graemlins/grin.gif" alt="" /> <img src="/ubbt/images/graemlins/grin.gif" alt="" /> <img src="/ubbt/images/graemlins/grin.gif" alt="" />

BTW GC, NZ is the PERFECT place for you to finish your doctorate. We have a big hole in the ozone layer right above us, we are suffering extremes of weather right now (the lower half of the South Island is blanketed in thick snow down to sea level - very unusual - not the snow, but the extremes of snow) and we in the north are being buffeted by icy blasts straight from the South Pole (not unusual for this time of year).

Global warming is very much in the news down here.

I could do with some right now actually. It's hailing outside.

I have it on good authority that the Mother Ship is from Uranus. Therefore, Venus might be a more appropriate destination. <img src="/ubbt/images/graemlins/laugh.gif" alt="" />

Who's seen the "Futurama" where Professor Farnsworth says,

"Astronomers renamed Uranus to end that stupid joke once and for all."

"What did they name it?" Fry asks.

"Urectum", says the Professor.

GC

Thanks for the information Gray.

Most of it anyway. <img src="/ubbt/images/graemlins/blush.gif" alt="" /> <img src="/ubbt/images/graemlins/blush.gif" alt="" />

SS