Saturday, April 18, 2015

More About Cumulative Warming, Models versus Observations

This is more about how well (or not) climate models predict/project the total warming that's been seen so far.

After I put up this graph of a GISS model's cumulative warming versus observations, a couple of people said "but it's just one model." Fair enough. It happened to be the first model I looked at, because I'd been reading a paper about it.

The same CMIP5 page also has a data file for an ensemble of 21 model -- presumably, the "best" ones, the biggest ones, made by the big research groups. (All models aren't created equal, which makes one wonder about this Roy Spencer graph with an average of 90 models. More about that graph at HotWhopper.)

Here's the result for the total warming from 1860 to 2014:


C&W is Cowtan and Way. Again, by "total warming" I mean (linear slope)*(time interval). (Not perfect, but what would be better? Maybe average_of_last_30_years - average_of_first_30_years. Maybe I'll try that later.)

So, the agreement is pretty good. The deviation between the ensemble mean and Cowtan & Way starts around 2005, and is now up to 0.07°C. There's your slowdown.

If I was Stephen Koonin, I would say the model error is only 0.07 K/288 K = 0.02%. But I'm not, so I won't.

Instead, it's about 0.07 K/0.94 K = 7%, over a century and a half.

So how good does a model need to be?

Friday, April 17, 2015

NOAA Gets Warmer

NOAA found the average global temperature anomaly for March to be the warmest for any March in their records, and the third-warmest of any month since 1880 (after only the tie between Feb 1998 and Jan 2007).

Here's how warm it's been in recent months: NOAA's record year was also 2014, with an average anomaly of +0.69°C. For this year to match that record, the rest of 2015 has only to average +0.65°C, which is 0.17°C below what's it's averaged so far.


Note: NOAA uses a baseline of 1901-2000, so their numbers aren't directly comparable to GISS (1951-1980) or HadCRUT4 (1961-1990). But trends are directly comparable, as are differences between months.

Thursday, April 16, 2015

Tuesday, April 14, 2015

See Steyn Lie

In another post by a climate expert, Mark Steyn writes:
"As I've said before, if you graduated from college last summer, there's been no "global warming" since you were in kindergarten."
This is getting so bad now this can only be called what it is: a lie. Purposeful deceit. Scientific fiction.

Blatantly, it ignores ocean warming, the best of all indicators of global warming. (As they say, it's called "global warming," not "surface warming" and not "only-RSS-and-no-other-datasets-allowed warming.")

The correct statement is:
If you graduated from college last summer, you've just lived through the warmest 12 months of your life. And of your parents' lives, and your grandparents' too.
I hesitate to confuse Steyn with numbers, but... assuming one is 5 years old in kindergarten, and 22 when they graduated college last summer (so most people would be 23 at this piont), that's the cherry picked "18 years."

So let's look at NASA GISS's temperature anomaly since Jan 1997:


Or this, showing the last 12 months are the warmest such period in GISS's records:


Of course, those looking to fool others like to pretend the only data that exists anywhere in the world is from RSS:


while completely ignoring the other data that measures the same thing, but which has better coverage of the globe (UAH misses 0.9% of Earth's surface; RSS misses 6.9%).


I won't even get into error bars and statistical significance and all that -- it would pass through Steyn as just more dark energy. Or Cowtan and Way (trend of +0.11 C over 18 years.) Or ocean warming, the best of all indicators of global warming. Or the role of natural variability, or that 18 years is too short to be indicative of climate change anyway. 

The liars like Mark Steyn don't want to hear anything about all that. Climate science is, for him, just another thing to hate on, another faucet for his bile.

What Hiatus?


Data:
http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt

NASA GISS: March was 5th Warmest Month in Their Record

GISS's March anomaly was +0.84°C, the 5th warmest (most anomalous) month since 1880.

It was the 3rd warmest March. The Northern Hemisphere (+1.17°C) was the warmest March in the records, and the second-highest of any month in the NH.

My guess (+0.86°C) was again pretty good.

Recent temperatures are climbing, and now approach the peak of the 1997-98 El Nino:

Nino3.4 anomaly on left-hand axis; GISTEMP anomaly on right-hand axis.

April 2015, however, is looking like it will have a signficant anomaly drop of perhaps 0.2°C - 0.3°C, based on the first half of the month. More on that later.

Monday, April 13, 2015

Velella velella Wash Up on Oregon Shores

Blown onshore by strong westerly winds. Beautiful, in its way:



Velella are free-floating hydrozoans, somewhat like jellyfish. Most less than 7 cm long. (Hard to get a scale on this photograph.) Via the Oregonian.

Thursday, April 09, 2015

On "Is Climate Change Making Us Stupid?"

Two things caught my eye tonight. One was this Tweet by Roger Pielke Sr
motivated by this post by Judith Curry, "Climate change availability cascade," where she concludes
Is climate change making us stupid? I fear that the answer is ‘yes.’ This problem is exacerbated by politically correct climate change orthodoxy, enforced by politicians, advocates and the media in an availability cascade, which is destroying our ability to think rationally about how we should respond to climate change. As a result, we have created a political log-jam over this issue, with scientists caught in the cross-fire.
Most scientists are caught in the cross-fire. But some are doing the shooting. (And, no, I'm not naive enough to think the bullets are only going in one direction, either, but I do see an asymmetry.)

Personally, I'm getting very tired of being called stupid, hearing people called stupid, hearing scientists called stupid, and the media, and advocates, and Barack Obama, and the left as a whole. I'm getting tired of hearing that the scientific process has been "corrupted."

I'm getting tiring of hearing people, especially certain scientists, whine about “politically correct orthodoxy,” that there's no ability to think rationally (besides the ones making the claim, of course), that scientists are climate zombies, that the fix is in. It sounds like what it is -- nothing more than an excuse because these scientists' own ideas aren’t being widely accepted, their op-eds aren't convincing, they're not winning the debate, their science isn't more convincing. That's playing politics, the very thing they claim to see in others. And it’s playing the victim, which is always kinda pathetic.

It’s very simple for these scientists to fix the situation they're complaining about — provide better evidence. Put forth better science. Gather data and write papers than convinces others your ideas have merit, that what you’re claiming is real and right and that a different viewpoint is therefore required -- required because that’s what your evidence shows and your science says, not because you wrote some polemic on your blog or on Twitter.

Better evidence has always prevailed in science -- in fact, it's the only thing that ever has -- which is the real story of those peptic ulcers.

But stop maligning scientists as a group, stop whining they’re suppressing ideas, that the game is rigged, that those who accept the seriousness of AGW position are climate zombies. Stop saying everyone (besides you) is doing it just for the grant money, except for all the secret people you know who all support your position but they're too afraid to come out and say so because they have a mortgage.

Science is, and always has been, a battle of ideas, and not all ideas are created equal and not all ideas prevail. I'm not a scientist, but it seems to me you have to fight for your ideas, fight hard, but fight honorably, and if you don't win a battle, turn around and get up and head back in, but don't complain endlessly that the other side is cheating. They're not cheating. They're not stupid. They're not corrupt. And you're not fooling anybody.

Wednesday, April 08, 2015

Discussion of How Global Warming Works

This is a post whose comments will be a discussion of things I'm discussing with someone on Twitter (to take it off Twitter and its character limitations).