Is Global Warming Unstoppable?

Well, just to keep the thread clean:

No actual climate scientists expect there to be any "slow steady increase in temps." No-body. None. Nuh-uh. No climate scientist says that. In fact, they say the opposite: You should expect significant short-term deviations around trend, for a wide variety of reasons. So, just to be clear, when you see the argument that the lack of slow steady warming is a reason to think that this is just natural cycles, what you're looking at is a straw man.

When you see somebody wave their hands and say, look, no trend -- without actually showing the calculated trend -- you should probably take a few seconds and find the data with the trend actually estimated, as here. (Note that they didn't include the earliest years. You can read the entire associated webpage if you want to try to understand why that is, here:

File:Satellite Temperatures.png - Wikipedia, the free encyclopedia

Or read up on the many adjustments that have been required to get usable information from the satellite data, here:

RSS / MSU and AMSU Data / Description




Climate scientists don't make inferences about temperature trends by comparing one month to another. But if they did, they wouldn't cherrypick the end month, but instead would use the most recent month available, even though that does not particularly make their point. So, instead of 0.001, plug in 0.28 for the most recent month of satellite data. Still below trend, but not as eye-popping.




Criminey, even the guy who puts together the graph that was cited agrees that the earth is warming. He doesn't say "no trend", he says it might be a hypothesized very-long-term natural phenomenon. He just doesn't think its due to C02. I won't go into the reasons why his view is (rightly) not mainstream, but his "favorite candidate" for a natural cause is the hypothesized "pacific decadal oscillation". Which you can google if you want to learn about it.

Global Warming 101 Roy Spencer, Ph. D.


It would be nice to have a reasoned discussion of (e.g.) the importance or lack thereof of the pacific decadal oscillation. If we wanted to discuss possible "natural cycle" alternatives to C02. But somehow I don't think that's going to happen here.

(EDIT: I take that back. There's a decent discussion of the issues no the NASA website that pretty much convinces me that the PDO doesn't explain the trend, here:

http://www.giss.nasa.gov/research/briefs/delgenio_05/
)

Anyway, if one were to want to use the satellite data from Univ Alabama Huntsville (as opposed to other temperature constructions from the satellite data) it would make more sense to look at the change in decade averages. The raw data is here:

http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt

At the bottom, they list a trend of 0.13 (degree C per decade, I'm pretty sure). Odd, that would appear not to be the most recent correction of the data, even though I got the link from Dr. Roy Spencer's website. Anyway, that's below what the ground-based series show, but see the discussion of issues with the satellite series (and other temperature reconstructions from these data show a higher trend).

But the sensible way to look at the data is to compare long-period averages. Here are the global average temperature anomalies for three successive decades (120-month periods) ending in October 2009, based on the Spencer and Christy satellite data above:

Decade ending oct 2009: 0.216
Decade ending oct 1999: 0.058
Decade ending oct 1989:-0.046

Just so there's no uncertainty about interpretation, the midpoint of the first decade and the midpoint of the last decade are 20 years apart. The apparent trend, based on those three datapoints, is 0.131 degree C per decade, exactly as published with the data.

That's probably a better way to look at the data than to pay attention to every short-term rise and dip.

Remote Sensing Systems has an alternative temperature construction from the satellite data, here:

ftp://ftp.ssmi.com/msu/monthly_time...hannel_tlt_anomalies_land_and_ocean_v03_2.txt

Doing the same decade analysis there yields:
Decade ending oct 2009: 0.255
Decade ending oct 2009: 0.081
Decade ending oct 2009: -0.064

The same analysis with their temperature construction from the satellite data shows a trend of 0.16 degrees C per decade (Again, the midpoints of the first and last decades are 20 years apart).

I have read that other reconstructions of temperature from the microwave satellite data yield yet higher estimated trends, but I have not actually seen those reconstructions.

Either way, if you'll step back from the monthly fluctuations and take some reasonable long-term averages (consistent with looking at climate, not weather), it's hard to use the satellite data to make any case other than that the current decade is warmer than the prior decade.

I probably ought to say that there may well be long-term fluctuations (in something, it's not clear what, exactly) analogous to the El Nino/La Nina. If so, if they are large enough, and if they are not offsetting (e.g., the Atlantic being out of synch with the Pacific, etc.), they could alternatively enhance and mask the ongoing trend driven by greenhouse gas buildup. But El Nino doesn't generate heat, and neither would these cycles. The presence of cycles would not change the basic physics of the situation. The smartest available calculation still says that there's a radiative imbalance due to GHG buildup. The new equilibrium will be hotter. It may be an uneven ride to getting there, but rises and dips don't make the underlying problem go away.

As with all alternative explanations, anyone who says that some natural cycle is causing the current trend has offered an incomplete situation. A complete explanation has to show that the alternative is causing temperatures to rise, *and* show why all the detailed calculations about the effects of GHGs and other forcings are wrong. In so many words, you'd need to show what you think the root cause is, *and* show that C02 isn't a greenhouse gas, or point out the flaws in the radiative balance calculations that lead most climate scientists to the conclusion that the current temperature trend is being driven by the GHG increases (net of the effect of other forcing factors such as aerosols, land use change, etc.)

 

The chart is interesting because it show no trend whatsoever from 1979 - 1997.

- Why nearly 20 years without any warming from '79-97?
- Why all of a sudden a step change in temperatures post 1998 El Nino?

How is this step change the result of CO2?

Yes, the earth is warmer by these measures during most of the current decade than the last, but AGW as an explanation here just does not cut it.

 

How about natural temperature variation?

 

Most probably.

 

The original post accepts the notion that the human emission of CO2 drives 'global warming'. This is an erroneous view. How can one say this?

Global Fossil-Fuel CO2 Emissions

Global Fossil-Fuel CO2 Emissions

Graphics Digital Data (ASCII, Fixed Format) Digital Data (ASCII, Comma-delimited)
Trends

Since 1751 approximately 329 billion tons of carbon have been released to the atmosphere from the consumption of fossil fuels and cement production. Half of these emissions have occurred since the mid 1970s....

I'm not a scientist. I do lay claim to a certain amount of common sense. If fully ONE HALF of anthropogenic CO2 released into the atmosphere since 1751 has occurred since the mid 1970s, doesn't this suggest that there should be a demonstrable dramatic rise in temperature during that period? (Assuming the hypothesis put forward by IPCC and the notorious 'consensus' we are always hearing about.)

Without manufacturing it, that dramatic rise is not there. Since coming out of the Little Ice Age, temperatures have been on a gentle upward slope with perturbations above and below it. We've had thermometers since, what, the 1880s. Global temperature, instrumentally measured and without the need for proxies demonstrate this gradual increase. Nothing unusual has happened since the mid 1970s to validate the IPCC hypothesis.

Case Closed.

 

And that's exactly what we have. The graph you constantly show starts on 1979. You have to compare pre-70s temperatures to current.

 

And yet by your own definitions, Alric, AGW has been disproven

 

When did that happen?

 

Wow. The other global warming thread got closed. Pretty ridiculous if you ask me. The AGWers were going around insulting people, telling us to jump off cliffs, and the moderator knew less about the issues than anyone else, and the thread gets closed.

Silencing people won't make the reality of this great hoax go away.

Hopefully in this thread the AGWers can discuss without just insulting.

 

Yes. I can see how graphs and data can be insulting to you.

 

You know, all the posts with TimBikes, where you had said 40 or 50 years of cooling would disprove AGW, and we had periods of 40-50 years of cooling. Therefore by your own definition AGW was disproven. Let's not forget the half dozen posts of ufourya's you still need to reply to in the closed thread. Feel free to copy and paste over to this one

 

Please keep the discussion mature.

 

Where are the 40-50 years of cooling?

I responded to him and Timbikes many times and they would just keep asking for me to answer.

http://priuschat.com/forums/environ...man-based-global-warming-201.html#post1011615

 

OK Alric - I'll give you the benefit of the doubt, though I don't remember you answering why 40 years of cooling does not falsify AGW when you said quite clearly it would. I remember you saying something about "well, the co2-temperature relation is not exactly linear so you won't see the warming happen at the same time as the temperature increase".

But isn't that what Algore claims? Isn't that what the warmists say when they look at the 1990s and claim temperatures rose in "lock-step" with CO2? Certainly you've heard that one - right? "Lockstep"?

And isn't it clear from this chart that even over a longer period of almost 50 years (~1930-~1980) that there is no discernible warming despite your own argument that there should be?



So for everyone's benefit Alric, please explain again how this 50 years of cooling in the face of rapidly rising CO2 does not falsify AGW as you argued it would?

 

That's US temperature.

 

I see it as well.

Recent disclosures of malfeasance render ny graph which includes data or work by Jones and Mann an insult to science.

 

Not Science yet, but Nature has published their opinion on the emails:

"Nothing in the e-mails undermines the scientific case that global warming is real — or that human activities are almost certainly the cause. That case is supported by multiple, robust lines of evidence, including several that are completely independent of the climate reconstructions debated in the e-mails.
And again:
The stolen e-mails have prompted queries about whether Nature will investigate some of the researchers’ own papers. One e-mail talked of displaying the data using a ‘trick’ — slang for a clever (and legitimate) technique, but a word that denialists have used to accuse the researchers of fabricating their results. It is Nature’s policy to investigate such matters if there are substantive reasons for concern, but nothing we have seen so far in the e-mails qualifies."

Climatologists under pressure : Article : Nature

 

The questionable graph you posted is Northern Hemisphere only, so your point to Tim is supposd to make what point?

 

The northern hemisphere is slightly larger than the US...

 

How many times is a skeptic going to post US-only temperatures and use it to make a conclusion about global warming?

You can be a skeptic all you want, but this kind of kindergarten error -- carried out and corrected on an almost-daily basis -- belies your supposed earnestness.