July 1936 now hottest US month again!

The latest story on all the global warming denier blogs is that July 1936 is the hottest month in the US again. July 2012 was the hottest month in the US for a while, but the figures have apparently, according to wattsupwiththat, been "adjusted", "as if by magic".

Watts goes on to say:

This isn’t just some issue with gridding, or anomalies, or method, it is about NOAA not being able to present historical climate information of the United States accurately. In one report they give one number, and in another they give a different one with no explanation to the public as to why.

Thus proving himself a clown, because if you look at the page Watts got his graph from (NOAA Climate at a Glance), it states very clearly:

NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. 

And it doesn't take much research to find that this is an issue with gridding, that NOAA have explained to the public why it happened, and that Watts is talking out of his bottom when he claims it happened "as if by magic".

The switch to the GHCN-Daily-based dataset has little effect on the average national temperature trend or on relative rankings for individual years. This is because the new dataset is based on gridded anomalies produced using the same set of algorithms and corrections that are applied in the production of the USHCN v2.5 dataset. However, although both the USHCN v2.5 and the new gridded dataset yield comparable trends, the finder resolution dataset more explicitly accounts for variations in topography (e.g., mountainous areas). Therefore, the baseline temperature, to which the national temperature anomaly is applied, is lower (cooler) in nClimDiv than in the USHCN v2.5. This new baseline affects anomalies for all years equally, and thus does not alter our understanding of trends.

NOAA National Overview - January 2014 New CONUS Temperature Dataset

1936 is now 0.03 degree hotter than 2012, where previously 2012 was 0.2 degree hotter than 1936.

The reason this is so significant for global warming deniers is they like to use the fact that the US was warmer in the 1930s as an excuse to dismiss the reality of global warming, just as they like to use the claim that the world was warmer in the Medieval Warm Period.

It looks from the graph above that the US has been warming over recent years, so the deniers may not have long to enjoy the renewed status of 1936 as the warmest year, but let them relish 0.03 of a degree for as long as it lasts.

The Pause may pause

Christopher Monckton is claiming there's been no global warming for 17 years and 9 months based on the latest RSS satellite data. (Link)

Graphic: Wood For Trees.

The claim is rubbish, of course, for the simple reason that this period begins with a super El Nino and ends with a couple of strong La Ninas. If there were no warming, the trend over this period should have been cooling; that it is flat should tell you that there is warming going on.

Monckton seems to understand that the trend will turn positive with the next El Nino event (probably later this year), as the El Nino adds warmth to the atmosphere (hence the title of this post, his words, "the Pause may pause".

But he adds "it may well resume late in 2015."

It's wishful thinking.

As the years pass, El Nino years become warmer and La Nina years less cold, as the full RSS data set shows.

The further we move away from 1996, the more El Nino years will produce a stronger warming trend, and the less La Ninas will bring it down. Not unless the next El Nino is a lot weaker than expected, and the next La Nina exceptionally strong will the trend return to a flat line: it's going to creep up over time, even though it may take 15 years more before a moderate el Nino year is going to equal the temperature of the 1998 super El Nino.

We are at the end of the "Pause".

Monckton makes another point that warming is less than expected by the models, which is true.

A comment to his post has a useful link to an RSS analysis, (from which the above graph comes).

The reasons for the discrepancy between the predicted and observed warming rate are currently under investigation by a number of research groups. Possible reasons include increased oceanic circulation leading to increased subduction of heat into the ocean, higher than normal levels of stratospheric aerosols due to volcanoes during the past decade, incorrect ozone levels used as input to the models, lower than expected solar output during the last few years, or poorly modeled cloud feedback effects. It is possible (or even likely) that a combination of these candidate causes is responsible.

 But that's a different kettle of fish.

The US is cooling!

This claim is the latest hot denier meme. It's rubbish of course, from a global warming bozo called Steve Goddard, but it seems it's not stupid enough, so a pair of even bigger bozos called James Delingpole and Christopher Booker have turned it into

Global Warming 'Fabricated' by NASA and NOAA

and

 The scandal of fiddled global warming data

The claim is based on the difference between the USHCN Version 1 USHCN Version 2 data sets of US temperatures illustrated in these graphs, combined into an animation:

The animation is a bit dishonest, because it doesn't include the recent data, so here is my own version:

Looking at the first animation, you might get the impression that higher temperatures at the end of the graph are the result of "NOAA/NASA Dramatically Alter[ing] US Temperatures After The Year 2000". Well, no, they are not: they are the result of warming temperatures in the US.

There is a difference between the two data sets up to 2000: a drop mid century and a rise at the end of the century in the second data set. The rise at the century is because (among other factors) "there has been a widespread conversion from afternoon to morning observation times in the USHCN", which is documented in the scientific literature. NOAA National Climate Data Center.

The warming bias is about 0.2 of a degree, visible around 1990/1995, but notice that average temperatures rise by 0.5 of a degree after that, with the maximum rising by a whole degree: in fact, the latest graph has a new line to fit this new datum, with it's scale rising to 2.0 degrees.

This was of course 2012, the warmest year in the US. Apparently just by leaving this year off the graph the climate change clowns can forget about the heat waves and record temperatures of that year and convince themselves that the US is cooling!

Compensating for a well documented change in time of day of observation in temperature data is not fiddling or fabricating data. Would anybody argue seriously that ignoring this factor gives a more accurate picture of how temperatures have changed?

But there is no serious argument from global warming bozos of course, just stupid conspiracy theories, endlessly echoed by bozo journalists and bloggers.

And I haven't even asked how US temperatures supposedly cooling is taken to mean that global warming is in question.

With each echo, the stupidity grows and the accusations become more clownish.

Aerosols cause global warming!

This is what global temperatures would look like if the aerosol cooling effect dominated over CO2 warming. High aerosol production as a result of global industrialisation would have resulted in cooling temperatures, until attempts to deal with acid rain reduced aerosol emissions in the latter twentieth century.

In fact, temperatures look like this:

Climate science concluded in the late 1970s that CO2 warming would dominate aerosol cooling, so who would be foolish enough to imply the opposite?

A global warming bozo, of course:

A 5-10% decrease in solar energy received at the Earth's surface due to aerosols is huge [up to 136 W/m2], and far more than the ~0.5 W/m2 increase alleged due to man-made greenhouse gases since the beginning of the industrial revolution. A mere 1-2% change in global albedo from clouds/aerosols is sufficient to tip the balance between global warming or cooling.

The Hockey Schtick, referring to Global aerosol change in the last decade: An analysis based on MODIS data.

Global warming deniers love to talk about global cooling, and no warming for 10 years, but the paper the Hockey Schtick cites says aerosols have decreased over the last decade, so shouldn't temperatures have gone up?

Volcanoes are melting the Antarctic

My first three climate change clowns have looked a paper in the Proceedings of the National Academy of Sciences of the United States of America called Evidence for elevated and spatially variable geothermal flux beneath the West Antarctic Ice Sheet and made some very clownish statements:

Uh oh: Study says ‘collapsing’ Thwaites Glacier in Antarctica melting from geothermal heat, not ‘climate change’ effects

wattsupwiththat

WAIS outlet glacier being melted by magma – not co2 global warming after all

tallbloke

Why the West Antarctic Ice Sheet Is Really Melting. (No, It's Not 'Climate Change')

James Delingpole

The paper itself says nothing about climate change or CO2, which news reports in the general media have reflected accurately.

"Before our paper, models tended to just assume a uniform geothermal flux value beneath the glacier because it was the best you could do with the observations available (even though the presence of nearby volcanoes and other geologic evidence suggested it was probably very non-uniform).

abc.net

Now, a new study finds that these subglacial volcanoes and other geothermal "hotspots" are contributing to the melting of Thwaites Glacier, a major river of ice that flows into Antarctica's Pine Island Bay.

Researchers have long known that volcanoes lurk under the ice of West Antarctica. This is a seismically active region, where East and West Antarctica are rifting apart. In 2013, a team of scientists even found a new volcano beneath the West Antarctic Ice Sheet.

West Antarctica is also hemorrhaging ice due to climate change.

 foxnews.com

The scientific press is clear about the reason the west Antarctic ice sheet is melting:

The glacier is retreating in the face of the warming ocean and is thought to be unstable because its interior lies more than two kilometers below sea level while, at the coast, the bottom of the glacier is quite shallow.

phys.org

The effects of global warming on the west Antarctic ice sheet have been in the news recently, with scientific studies suggesting warming has pushed the sheet over a tipping point, leading to an inevitable (albeit after 200-500 years) collapse.(See 'Nothing can stop retreat' of West Antarctic glaciers, BBC News.)

Which is probably why the climate change bozos are trying to misuse this latest PNAS paper to suggest that it's just natural warming.

As if these volcanoes suddenly appeared and are melting the ice!