Friday, January 19, 2018

Graphs of 2017 global temperatures among record years for major indices

A few days ago, I posted some graphs in an updated style which shows 2017, as seen by TempLS mesh in its place among records years (2017 came second) in a progressive record style. I also showed a detailed graph of the sequence of months from 2014 to 2017, showing how the warming introduced by the El Niño seems to be lasting. I said I would do a similar set of plots for the major indices when they appeared, as I have done in previous years. By now NOAA, HADCRUT and GISS have reported, as well as the satellite indices. So here is the set of progressive record plots. We have so far:
  • GISSlo - Gistemp land/ocean
  • HADCRUT 4 land/ocean
  • NOAAlo - NOAA land/ocean
  • UAH V6.0 - lower troposphere (TLT satellite)
  • RSS V4.0 - lower troposphere (TLT satellite)
  • CRUTEM 4 - land only
  • TempLS mesh
I'll add more as they arrive. You can find more information about the indices, with source links, here. The Glossary may help too. You can flick through the 7 images using the buttons below the plot.

GISS and TempLS had 2017 in second place, as did RSS V4.0. HADCRUT, CRUTEM and NOAAlo put it behind 2015 in third place. UAH V6 had things in a very different order, with 1988 in second place, and 2017 a distant third. The grouping of the surface indices is commonly observed. TempLS mesh and GISS interpolate, giving more (and IMO cdue) weight to polar regions. NOAA and HADCRUT do so much less. So insofar as the warmth of 2017 was accentuated at the poles, the less interpolated indices tend to miss that.

Here is the set of monthly averages for each of those indices, with as before the annual averages shown as horizontal lines in the appropriate color. Almost all months of 2017 were well above the 2014 average, even though 2014 was a record year in its time.

GISS December global up 0.02°C; 2017 was second warmest.

GISS warmed slightly, going from 0.87°C in November to 0.89°C in December (GISS report here). That is very similar to TempLS mesh; I originally reported no change, but later data pushed that up to a 0.04°C rise. For GISS, that makes 2017 the second warmest year in their record; behind 2016 but ahead of 2015. Their report, with the annual summary too, is here. I showed some aspects of 2017 annual in context here, and I'll do that for GISS and other indices in an upcoming post.

The overall pattern was similar to that in TempLS. Cold in east N America and Mediterranean and far East Siberia. Very warm in most of Russia, and in the Arctic. A cool La Nina-ish plume, but warm in the Tasman sea.

As usual here, I will compare the GISS and previous TempLS plots below the jump.

Wednesday, January 10, 2018

Review of 2017, heat records, and recent warm years.

Yesterday I posted the December global anomaly (base 1961-90) results for TempLS mesh, and noted that it made 2017 the second warmest year, after 2016. I'd like to put that in a bit more context. For the last three years (eg here) I have posted a progressive plot showing in steps the advance of the hottest year to date. Since 2014, 2015 and 2016 were each the hottest years to date, there was something new to show each year, and the plot showed the rapidity of those rises. This year, with 2017 in second place, it doesn't add new information to that style of plot. So I tried a way of adding information. I superimposed on the steps plot a column plot of each year's temperature. This measn that you can follow the max outline, or focus on the columns, which also show how far the years following a record were cooler. It emphasises the warmth of 2017 relative to earlier years. Here is the plot:

The legend shows the color codes for the record years. I'll probably make an active plot of all the indices when they become available. But I was also curious about how 2017 came to be warmer than the near Niño year of 2015. So I drew a column plot by month of the last four years, shown by color
I've also marked each year's average in the appropriate colour. 2017 is almost a mirror image of 2015, and the main contribution to its warmth came from the first three months, a somewhat separate peak from the El Niño. But what is clear is that the apparent level of later 2016 and 2017 is a good deal higher than 2014, a record year in its day. Even the coolest month of 2016/7 (June 17) was at about the 2014 average.

In my previous post, I reported December 2017 as virtually unchanged from November. Further data has made it a little warmer. In other news, the Australia BoM 2017 climate statement is out, and here 2017 was the third warmest year, after 2013 and 2005.

Tuesday, January 9, 2018

December global surface temperature unchanged; 2017 was second warmest year.

TempLS mesh anomaly (1961-90 base) was virtually unchanged, from 0.716°C in November to 0.721°C in December. This compares with the rise of 0.075°C in the NCEP/NCAR index, and a similar rise (0.05) in the UAH LT satellite index.

The TempLS average for 2017 was thus 0.757°C, which puts it behind 2016 (0.836°C), and ahead of 2015 (0.729°C), and so was the second warmest year in the record. I expect this will be a common finding, although 2015 is close. I'll post a graph showing the history of records.

The breakdown is interesting. The main cooling effect came from SST, well down on November. The balancing rises came from the Arctic and Siberia. Since TempLS, like GISS, is sensitive to Arctic temperature, indices like NOAA/HADCRUT may well show a fall. Otherwise the map shows those effects, along with much-discussed cold around the Great Lakes region and also W Sahara.

Here is the temperature map:

Thursday, January 4, 2018

December NCEP/NCAR global anomaly up 0.075°C from November

In the Moyhu NCEP/NCAR index, the monthly reanalysis anomaly average rose from 0.253°C in November to 0.328°C in December, 2017, making it a mid-range month for 2017. The temperature did not oscillate as much as in some recent months.

The main cool spots were Canada and E Siberia, NW Africa (Algeria) and Antarctica. East Europe and NW Russia were warm, and also Alaska and a band through the Rockies, S Calif. There was a notable warm spot in the seas around New Zealand.

The annual averfage for 2017 was 0.376°C. This puts it behind 2016 (0.531) but ahead of 2015 (0.330) and 2014 (0.190).

Friday, December 29, 2017

Upgrading Moyhu infrastructure

I have spent part of the holidays tinkering with Moyhu's infrastructure. I keep copies of all posts and pages offline, partly for backup, and partly so I can search them and also make universal changes. This was of great value when Blogger required use of https a couple of years ago.

I was trying to revive the graphics gallery page, which never really recovered from that change, since it used copies of posts, which also need fixing. But I got side-tracked into upgrading the interactive topic index. I don't think readers use it much, but I do. Google provides a search for the blog, but it returns a display of complete posts, so needs precise search terms. The interactive search just returns a list of linked titles, so you get a wider sweep (maybe too wide).

The new index looks like this (non-functional image):

I had clicked on the Marcott button, and the list of links (with dates) appears below. The topics have been extended, and groups in to color-coded types. The types are listed on the left. I have extended the topics considerably. They mostly work by a keyword search, so you get some false positives. I added some at the end (housekeeping, debunkings) which don't have natural keywords, and were manually identified. And I have separated out the three series of monthly postings that I do (NCEP/NCAR, TempLS and GISS). It makes them easier to find, but because I exclude he keyword search for them, it reduces the false positives.

The new arrangement should be much easier to update regularly.

I have also added a blog glossary. We're used to tossing around terms like CRUTEM, but not everyone is, so I have given a basic description (with links). I have added it to the bottom page , now called "More pages, and blog glossary". The more pages part is just a few lines of links at the top, and then comes the glossary. I'm sure it will need extending - suggestions welcome.

That was my New Year's resolution for 2017 :)

Saturday, December 23, 2017

Merry Christmas to all

Christmas starts early this year at Moyhu, so I'll take this opportunity to wish readers a Merry Christmas and a Happy New Year. Hopefully bushfire-free. In the spirit of recent examinations of past wildfires (Eli has more), I'll tell the story behind the picture above. The newspaper version is here.

In 2003 and 2006/7, alpine and upland Victoria were swept by long running and very damaging bushfires. The area concerned was rugged terrain and sparsely inhabited. Much was not so far below the snowline, so the trees there were not very tall, and the fuel somewhat less than for our wilder lowland fires. They were in summer, but not exceptionally hot weather, and of course cooler there. Consequently they burnt relatively slowly, with a fair chance of defending critical areas. Some were fought with great energy and danger to crews; this could not be expended everywhere, so they burnt for weeks and did much damage to mountain forests that take a long time to regrow.

In December, 2006, our most popular ski resort, Mt Buller, was surrounded by fires, again burning over long periods. Although as said the conditions did not make for extreme wildfire, any eucalypt fire is dangerous when it runs up a hill slope. The many buildings of Mt Buller sit near the peak at about 1500 m altitude, and there is a single winding road out, which became impassable on 22nd December. So the fire crews who had assembled were on their own. Fortunately, the resort had a large water storage used for snow-making. But there was a long perimeter to defend.

By the 23rd, flames were at that perimeter. I was at Buller the following winter, and saw that it had come right up to a northern edge road, with major buildings just on the other side. And it was pretty close on all sides. Fortunately, some rain came that evening, but still, there were more flareups on Christmas Eve.

At last, later on the Eve, more serious rain came with another change in the weather, and somewhat amazingly for our summer solstice, it turned to snow. That indeed marked the end of the danger to the mountaintop. In the morning, when they awoke to a very welcome white Christmas, this photo was taken.

Again, may your Christmas be as merry. With special hopes for those in the region of the Thomas fire.