## Tuesday, January 27, 2009 ... //

### Weather in the year 3000

Gene Day has sent me a cute article at MSNBC. Do you want to invite your friends for a barbecue party in the year 3000, a few years after the collapse of the Thousand Year Reich? And do you need to have plans for different weather scenarios?

Expect 1,000-year climate impacts, experts say.
Although science can only remove the noise and predict something specific about the atmosphere for a month in advance, while the behavior in any further future seems to be an intractable problem, the average experts got used to "predictions" of the weather for the year 2100 or 2200. No one is going to check these predictions during the people's careers - which is great - and because other people want to listen to them, anyway, these forecasts became widespread.

So if you want to be ahead of your climatological colleagues these days, 2100 or 2200 is not enough. So Susan Solomon is telling us that the catastrophe is going to be lasting.

Even if we stop all production of CO2, she says, the Earth will be "dying" at least until the year 3000 because the "murder" we are committing against Gaia is "irreversible". One of the greatest catastrophes is that the sea level will jump by 1 meter by the year 3000 just because of the CO2-related greenhouse heating expansion. What a cataclysm: it's almost a millimeter per year, roughly 10 times slower rate than when we were going out of the last ice age.

Moreover, it is extremely logical (for them) to talk about the year 3000 and use these speculations as a justification of an immediate "action", in the year 2009. There must exist a time machine or a wormhole between the year 2009 and 3000 if they can be linked in this way. Believe it or not, the fate of the people in the year 3000 depends on your decision on January 27th, 2009! :-)

She can't possibly be serious when she says that a 1 meter change of the sea level in 1000 years is bad. During the last 20 millenia, the sea level naturally jumped by 120 meters which is 6 meters per millenium. If you focus on the interval from 15,000 years ago to 7,000 years ago, the rate doubles. The rise was more than 10 meters per millenium. Relatively to these rates, the sea level rise nearly stopped 7,000 years ago or so.

Why did it stop so quickly? No, there was no discontinuity of the laws of physics. The reason was that the glaciers have disappeared from the bulk of the Earth's surface so there was no ice left to be melted - except for Greenland and Antarctica which might naturally melt (even without any human intervention) in a few thousand years, too.

You know, ice can sometimes naturally melt, lady!

It is no coincidence that 6,000 years ago or so, the ancient civilizations started to be born and flourish. The reason is that ice is pretty bad for life while the warming was damn good for them. Snow and ice are clean and cute but that's exactly why there's almost no life in them.

Sensible predictions and interpretations

It would be nice if people who are not hysterical crackpots like Susan Solomon were looking into these arguably speculative questions, too. What do I think about the climate in the year 3,000? Let me begin with the carbon dioxide - just because it is so popular these days.

For millions of years, the concentration fluctuated between 180 ppm (parts per million) during ice ages and 280 ppm during the interglacials. By additional industrial activity since 1800, humans were able to increase this number to 385 ppm or so. You can see that 8 °C of warming (after ice ages) increases the concentration by 100 ppm or so. However, additional 100 ppm only increased the temperature by 0.7 °C, more than 10 times smaller a number.

The reason is that the influence of the temperature on the trace gas concentrations (warmer oceans can't store much gas so they release it to the atmosphere - outgassing) has been much more powerful than the opposite influence, the greenhouse effect. We have talked about the 800-year lag many times. Temperature changed and the CO2 concentrations followed, approximately with a 800-year lag.

If you think for a while, this 800-year result is directly relevant for the debates about CO2 in the year 3000. What the 800-year observations tell us is that whenever the Earth is evolving in its "natural" way, it takes roughly 800 years (plus minus 600 years) before the trace gas concentrations almost exactly adapt to the concentrations predicted from the external temperature i.e. before the oceans absorb or swallow the excessive trace gases.

It may be expected that the "half-time" or "e-folding time" - in which the deviation of the concentration from the value predicted from the temperature reduces by a factor of "e" - is comparable to 500 years. So if we stop producing CO2 today, the CO2 concentration will drop back to 280+105/2.718 i.e. 319 ppm around the year 2500. Both plants and oceans will be absorbing the excessive CO2. You can also see that the CO2 concentration may stabilize even if we continue to produce it.

Boston's industrial suburbs, January 2100

What do I think about our production of CO2 in the future?

Well, I think it is likely that the mankind will consume most of the fossil fuels that are reasonably accessible and available, pretty much all of them, during the next 500 years.

Even if new technologies are found and propagate, the convenience of oil and gas (and perhaps coal) is indisputable in some contexts. The new energy sources will have other disadvantages and risks, so I am sure that the consumption of oil and gas won't ever drop to zero. Gadgets based on electricity and fusion may become fashionable in the richest and most snobby countries but others will continue to use some of the more "material" technologies based on oil. You know, certain disadvantages of electric cars (or electric airplanes?) etc. won't go away.

I estimate all the fossil fuels to be able to kick the CO2 temperature close to 1000 ppm. You know, it may be 700 ppm but I do think that it is likely that we will exceed 500 ppm (unless we will destroy intelligent life on Earth). As far as CO2 goes, the air outside will resemble your office today. There's no problem with that. Plants will be happier and people only begin to feel dizzy at 10,000 ppm.

1,000 ppm is almost 4 times 280 ppm, so one has to double the concentration twice. Because of the logarithmic law, the corresponding warming is twice the climate sensitivity. Because I think that the climate sensitivity is close to 1 °C, the burning of all fossil fuels will contribute by 2 °C of warming or so - and one third of it has already been made, without observing any negative consequences whatsoever.
Related: Joe Romm has admitted that The New York Times' Andy Revkin has been convinced to join the "deniers". Congratulations although the rest of the deniers will surely remain a bit cautious with Revkin. See Pielke. ;-)
You know, the IPCC "improves" the climate sensitivity to 3 °C, so the maximum warming obtained by burning everything could reach 6 °C. Clearly, if something like that were beginning to happen in the year 2200, they would have to think twice what they want to do and whether a flight to New York is going be more important than the 0.000001 °C of extra warming it will bring. Clearly, we're not facing these problems today and we won't face them in 2050 either and almost anyone who says that we are or we will is an out-of-equilibrium person who should join Jehovah's Witnesses, visit the neighbors, and tell them about the judgment day.

Now, the CO2 is extremely far from being the only major climate driver. Many other things may happen by the year 3000. The origin of the ice ages and interglacials may be astronomical. Or it may be the accumulated weather or changing life forms on Earth. But whatever it is, these cycles are guaranteed to continue.

Click (and find the second figure) to zoom in. This is the graph of temperatures (temperature anomalies in °C) in the last 400,000 years. You can see (on the left side of the graph, the present) that the ancient civilizations began when the Earth was roughly 8 °C warmer than it was 15,000 years ago. And if you look at similar peaks in the past, for example to the peak 120,000 years ago, it is clear that such warm periods never last indefinitely.

Mother Nature - namely whatever processes are behind the glaciation cycles - will eventually try to cool the Earth by 8 °C again. It would be preposterous to think that the natural variability that has been observed for millions of years would suddenly disappear, just because Barack Obama was inaugurated (or whatever reason the people could invent).

Again, the cooling by 8 °C into the new ice age takes roughly 10,000 or 30,000 years: it seems that no one can predict the graph accurately. But because of the random walk character of these graphs, a feature that seems to hold at all time scales shorter than 100,000 years, the temperature change per time "t" scales approximately like "sqrt(t)" (or at least, the best fit exponent is not far from 0.5). So in 1,000 years, you may expect a natural change by 3 °C or so.

If you look at the graph above, the cooling from the temperature maxima is often very fast. Surprisingly, the graph above suggests that the temperature maxima (warm periods) are usually "short-lived" (sharper). It may be because of the sudden expansion of a "bright" form of life or a form of life (whenever the temperature becomes too high) that uses a lot of solar energy for its metabolism (generally, I mean plants and especially the "bright" ones) and helps to cool the Earth quickly.

You see, the somewhat conservative estimate of a 3 °C temperature change per millenium - a figure we have quoted many times - trumps the changes caused by CO2, even if we burn all of fossil fuels. Clearly, if the people will burn all of it, the greenhouse warming may eventually become measurable and relevant. But there will never be a certainty that the following century will see a warming. Because of different contributions - and the looming return of an ice age will always be a negative one - there will only be probabilities.

Sensible scientists in the 23rd century will tell others that there is a 70% chance that the increasing CO2 emissions will guarantee that the 24th century is going to see a warming, while the probability of cooling, possibly a substantial one, will be 30%. Will it be enough for the rational people in the 23rd century to stop using airplanes based on old-fashioned fuels (which will take a lot of time to be replaced by something else)? I doubt it. Only if the trend "safely" beats the noise, rational people can be using it as an argument - at least in questions that will only be observed once during our lifetime.

While the greenhouse warming trend will probably be visible in the data by the year 3000, I am confident that it will never become large enough to "safely" beat the 50-year noise and other natural effects.

I am always amazed by the people who are ready to suggest e.g. that the sea level rise by 1 meter per millenium is a "lot" or a reason to reorganize the behavior of the mankind, if I use a modest formulation. ;-) Where do these feelings come from? Well, the answer is obvious. All these people are mollycoddled academicians who are guaranteed permanent salaries from the governments (i.e. taxpayers) and who spend their lives in perfectly air-conditioned offices with a constant temperature.

They have no idea about the real world. They have no idea about Nature where the average temperatures have been changing by 10 °C and sea levels were rising and dropping by hundreds of meters. They have no idea that conditions in Nature (and in the free markets) are dynamically changing in both directions. Most of them have no idea that the Universe began near the Planckian temperatures (10^{32} Kelvin) and the outer space is as cool as 2.7 K.They're just used to their static life that entirely depends on the government and they want to promote it into a law of Nature.

But their static life would be impossible if Nature didn't know what a chance means, if there were no people who actually work in different temperatures, under different oil prices and exchange rates, and whose convenient life is simply not guaranteed by the taxpayer. These people are the taxpayers themselves. These people have to produce values, heat, and entropy so that a "chosen minority" can consume the values, keep the temperature, and permanently lower their entropy. ;-)

But the pampered scholars don't see it. They think that the wealth and comfort is automatic and whenever it is not, it is because of an evil capitalist who has stolen wealth from the super-rich society based on primitive communism.

And that's the memo.

Update: 3000 is relatively recent

Willie Soon just pointed out that according to a very fresh article in Nature, Susan Solomon is so yesterday.

Gary Shaffer et al. argue that the burning of the fossil fuels will deplete the oxygen in the oceans until the year 102,009. ;-) The marine life will suffer, too.

These people are just sick. It is very clear that 800 years after the end of fossil fuels, the bulk of all the (modest) effects caused by the CO2 production will be undone, and if their computer tells them something else, they obviously don't know how to use computers.