Tuesday, May 24, 2016

More HTTPS - housekeeping

Wednesday, May 18, 2016

HTTPS and blogging

HTTPS seems to be coming to blogs. Most Wordpress sites have converted. Google is a big promoter. I think it is only a matter of time before Blogger sites come under pressure, though at the moment, that system is dragging its feet. So I have enabled HTTPS for Moyhu, and I'm writing about what it may mean for you. At present the likely answer is - nothing.

Personally, HTTPS seems to me to offer little and to have downsides. My enabling it does not require anyone to change the normal http: URL they use, and with no action they will see the usual response. If you use a https: URL (nothing else need change), then everything that appears on the page has to have a certificate. Since a great deal of stuff that has been linked in the past does not have that, unless I update the links, it won't appear. Worse, you may get a scary message saying that something has presented an invalid certificate, and someone may be trying to do you harm. Hopefully this won't happen, but if it does you'll know where it is likely coming from, and it is not a threat.

I've been watching the situation at Wordpress blogs, and did some commenting at this thread (scroll up for more). Wordpress has somehow made https mandatory. That is, whether you link with a http or https url, it is treated as https. To solve the problem of all the old images etc that don't supply certificates, they make their own cached copies with https url. The problem there is with locations that update content; the cached image doesn't change. Worse, the system intercepts links to such locations, and directs to whatever cache they have. You could find that you don't see what you thought you were linking to, but a copy that someone may have made on even a different WP site months ago.

Moyhu won't have that problem (as yet), because Blogger doesn't switch URLs, and also doesn't cache. So I will use entirely http links to past posts, and you should too. Again if you don't you'll see missing images, and maybe a scary message. For the moment I'm planning to restrict HTTPS linking to the home page and probably some heavily used pages like latest data and trend view.

Sunday, May 15, 2016

April GISS down 0.18°C - hottest April in record.

In fact, GISS first exceeded 1°C in October 2015, so until then everything over 1°C is a monthly record. October was 1.07, so April is getting back to that. GISS 2016 went from 1.29°C in March to 1.11°C in April. The drop in GISS was higher than other indicators; TempLS mesh was down 0.075°C (China increased it); NCEP/NCAR down 0.15°C. For the lower troposphere, RSS was down about 0.09°C, UAH down 0.02°C.

The Arctic was cooler, and GISS is sensitive to that. Other regional changes were much as discussed in the TempLS post. As usual, I'll show the GISS map and the corresponding TempLS below the fold.

In other news, Arctic Sea Ice is still melting fast..

Sunday, May 8, 2016

Surface TempLS global temperature down 0.104°C in April

TempLS mesh, reported here (as of 8 May, 4263 stations, China still to arrive), was down from 1.032°C in March to 0.928 in April (base 1961-90). This is slightly smaller drop than the NCEP/NCAR index (0.15), but larger than the satellite reductions(UAH 0.02; RSS 0.09). TempLS grid dropped by more (0.136°C), which is similar to NCEP/NCAR.

The spherical harmonics map is here:

Again unusually warm in Russia and W North America (except Labrador strait region). Not so warm in Arctic, cold over Hudson's Bay.

In the attributions plot, the main point of interest is that SST has risen again. The land pattern is similar to recent, but more subdued.

In other news, JAXA Arctic Sea Ice shows continued melting and record low levels; since mid April the margin between it and previous years has become quite marked.

Tuesday, May 3, 2016

April global NCEP/NCAR down by 0.15°C; still fourth warmest month

The NCEP/NCAR index that I calculate from their reanalysis was down by 0.147°C in April, from 0.783°C to 0.636 (anomaly base 1994-2013). That is then down 0.2°C from February, and coolest for 2016, but it still warmer than any month before 2016.

Temperatures have been stable near that average level since about March 10, after some very high earlier peaks. There was this time less warmth in the Arctic (except Greenland), but a broad band of warmth through Siberia, Eastern Europe, into Africa. Cold in NE Canada; patchy in Antarctica.

Among other reports, Karsten has GFS surface down from 0.794°C to 0.706°C. Roy Spencer has UAH 6 lower troposphere down slightly, from 0.73 to 0.71°C. ENSO numbers are down, and if you watch the ENSO movie of recent weeks, you can see the equatorial jet turning to cool.

Friday, April 29, 2016

GWPF inquiry anniversary.

Just over a year ago, the GWPF announced an inquiry into global temperature adjustments. There would be a panel of experts, chaired by Professor Terence Kealey. It was exuberantly promoted in the Telegraph - "Top Scientists Start To Examine Fiddled Global Warming Figures". Terms of reference were promulgated, and submissions called for, deadline June 30th. I made a submission, and wrote more about the process here.

As said there, the GWPF did mount a news page here. About three weeks after the submissions deadline, the panel said that they would not write a report, but would aim to write papers etc. The last update here was Sept 29, 2015.

So after a year, what has happened? Nothing more to report. The inquiry web pages are still up; submissions have not been published. No further news.

I have been reporting occasionally on progress; maybe I'll report again on the next anniversary, unless there is news in the meantime. But it sure doesn't sound like they have found those "Fiddled Global Warming Figures".

Friday, April 22, 2016

Averaging temperature data improves accuracy.

I've been arguing again at WUWT. It's a bizarre but quite interesting thread. There is a contrarian meme that asks how global averages can be quoted to maybe two-decimal accuracy, when many of the thermometers might have resolved to just one degree. I tried to deal with that here, showing that adding noise of 1°C amplitude to monthly averages made very little difference to the global average.

But the meme persists, and metrology handbooks get quoted - here a JGCM guide. But the theory quoted is for a single measurement, where repeated measurements can't overcome lack of resolution. But that isn't what is happening in climate. Instead a whole lot of different measurements are averaged.

Of course, averaging does improve accuracy. That's why people incur cost to obtain large samples. In this post, I'll follow my comment at WUWT by taking 13 months of recent daily max in Melbourne, given by BoM to 1 decimal place, and show that if you round off that decimal, emulating a thermometer reading to nearest degree, the difference to the monthly average is only of order 0.05°C; far less than the reduction in resolution. But first, I'll outline some of the theory.