Global warming is in the air, in the UAH lower troposphere

The UAH data for October is out. John Christy and Roy Spencer from the University of Arizona Huntsville have a contract with NOAA to analyse temperature changes in the atmosphere. Each month they publish the latest data.

Deniers dislike it less than other data sets, especially since John and Roy revised the latest version considerably downwards, making their data an anomaly!

I came across a chart I prepared a few years ago and thought I'd do it over again using the latest UAH data.

Not as hot June troposphere temperatures, with a new version from RSS

The troposphere temperatures for June 2017 are out. This report covers the lower troposphere as recorded in UAH v6 and the new RSS TLT v4, and RSS TTT v4 for the troposphere (without the "lower"). It follows pretty much the same format as previous monthly updates.

The troposphere is the part of the atmosphere directly above the surface. The temperatures are estimated from measurements recorded by satellites orbiting the earth.  They are not direct temperature measurements (the satellites don't record thermometer readings). And they are of an average of a depth of the atmosphere - up to several kilometres above the surface. The different versions of reported satellite temperature data tend to vary more than different versions of surface temperature.

For all three different temperature data sets shown, the 12 months to June 2017 is the second hottest 12 months in the record (comparing similar July-June periods).

• For RSS TTT (troposphere), June itself was the just the eighth hottest June, with June 1998 the hottest.
• For RSS TLT (lower troposphere), June was the equal fifth hottest June (with June 2014). June 2016 was the hottest.
• The lower troposphere (UAH v6) June was the eighth hottest June on record. June 1998 was the hottest.

No hiatus (or vacation) from denial - Anthony Watts and Ryan Maue misrepresent a new scientific paper

It looks as if Anthony hasn't yet left on his promised vacation his fans have paid for. Today he copied and pasted an article from, of all places, the Daily Caller (archived here, latest here). Now the Daily Caller is not regarded as a reputable source of scientific information. It's a right wing website from the USA, apparently widely read, particularly by Republicans seeking a daily outrage fix of sensationalised sentiment. (It's owned by a guy called Tucker Carlson, who replaced Bill O'Reilly at Fox. I gather there's not much to distinguish the opinions of the two.)

The shock and awe at WUWT is over a new paper by a team of scientific heavy-weights, led by the world-renowned climate scientist, Dr. Benjamin D. Santer. The paper, published in Nature Geoscience, reports an exploration of the reasons for any differences between modeled and observed temperatures in the upper air (the troposphere). The authors examined data for the satellite era, January 1979 to December 2016, which is when there were more reliable temperature observations of the upper air.

[Note: the paper itself is about troposphere temperatures. The charts I've added are surface temperatures, in part because I'm still short of time, plus I don't have model data for the troposphere to hand (Fig 3).]

Trending troposphere temperatures to May 2017

The troposphere temperatures for May 2017 are out. This report covers the lower troposphere as recorded in UAH v6 and RSS TTT for the troposphere (without the "lower"). It follows pretty much the same format as previous monthly updates.

For RSS TTT (troposphere), the 12 months to May 2017 is the second the hottest 12 months in the record (comparing similar June-May periods). Now that last year's intense El Nino has dissipated, May itself was the just the fourth hottest May, with May 2016 the hottest.

The lower troposphere (UAH v6) also showed the 12 months to May as the second hottest on record. However, in the UAH record, May was the third hottest May on record, after May 1998 and May 2016.

Not the hottest January in the troposphere, but way hotter than normal in the Arctic

The troposphere temperatures for January 2017 were released earlier this month. The lower troposphere is recorded in UAH v6 and RSS TLT v3.3. This report also covers RSS TTT for the troposphere (without the "lower") and follows pretty much the same format as previous monthly updates.

For RSS TTT (troposphere), the 12 months to January 2017 remain the hottest 12 months in the record (comparing similar Feb-Jan periods). January itself was the just the fifth hottest January, with January 2016 the hottest.

The lower troposphere (UAH v6) also showed the 12 months to January as the hottest on record. However, January was only the seventh hottest January on record, with January 2016 the hottest.

2016 was the hottest year on record for the troposphere

For the troposphere, 2016 was the hottest year on record!

The troposphere temperatures for December 2016 have been released. The lower troposphere is recorded in UAH v6 beta 5 and RSS TLT v3.3. This report also covers RSS TTT for the troposphere (without the "lower") and follows pretty much the same format as previous monthly updates.

For RSS TTT (troposphere), 2016 was the hottest year in the record. Last month was the second hottest December on record.

The lower troposphere (UAH beta v6.05) also showed 2016 as the hottest year in the record. However, December was only the sixth hottest December on record, with 2015 the hottest.

Hottest November on record for the troposphere - with a comment on Trumped Up Courage

Despite what David Rose, the Global Warming Policy Foundation, the fake press (Breitbart), WUWT, and the US House Science Committee will try to claim - global warming is real and happening now. There is no ice age about to arrive.

For the troposphere, November was the hottest November on record!

The troposphere temperatures for November 2016 have been released. The lower troposphere is recorded in UAH v6 beta 5 and RSS TLT v3.3. This report also covers RSS TTT for the troposphere (without the "lower") and follows pretty much the same format as previous monthly updates.

For RSS TTT (troposphere), last month was the hottest November on record. For 2016 to be colder than the previous hottest year (1998), the troposphere would have to average a negative anomaly:- less than -1.57 °C for the remaining month. It's an understatement to say that is unlikely.

The lower troposphere (UAH beta v6.05) was also the hottest November on record with 2015. For 1998 to remain the hottest year in the UAH lower troposphere record, the anomaly for December would need to be below minus 0.21 °C. That's not likely but not impossible.

Troposphere temperatures for October 2016 - another hottest on record

The troposphere temperatures for October 2016 have been released. The lower troposphere is recorded in UAH v6 beta 5 and RSS TLT v3.3. This report also covers RSS TTT for the troposphere (without the "lower") and follows pretty much the same format as previous monthly updates.

For RSS TTT (troposphere), last month was the hottest October on record. For 2016 to be colder than the previous hottest year (1998), the troposphere would have to average a negative anomaly:- less than -0.41 °C for the remaining months.

The lower troposphere (UAH beta v6.05) was the equal hottest October on record with 2015. For 1998 to remain the hottest year in the UAH lower troposphere record, the average for the next two months would need to be below 0.21 °C.

Another "hottest month": Troposphere temperatures for September 2016

The troposphere temperatures for September 2016 have been released. The lower troposphere is recorded in UAH v6 beta 5 and RSS TLT v3.3. This report also covers RSS TTT for the troposphere (without the "lower") and follows pretty much the same format as previous monthly updates.

In all records, the September global anomaly was higher than it was in August but lower than earlier this year as El Niño is now over.

For RSS TTT (troposphere), last month was the hottest September on record. For 2016 to be colder than the previous hottest year (1998), the troposphere would have to average a negative anomaly:- less than -.025 °C for the remaining months.

The lower troposphere (UAH beta v6.05) was the equal hottest September on record with 1998. For 1998 to remain the hottest year in the UAH lower troposphere record, the average for the next three months would need to be below 0.28 °C, which could happen. (Roy and John changed the August 2016 temperature, dropping it from 0.44 °C to 0.43 °C.)

Troposphere temperatures for August 2016

The troposphere temperatures for August 2016 have been released. The lower troposphere is recorded in UAH v6 beta 5 and RSS TLT v3.3. This report also covers RSS TTT for the troposphere (without the "lower") and follows pretty much the same format as previous monthly updates.

In all records, the August global anomaly was higher than it was in July but lower than earlier this year as El Niño is now over.

For RSS TTT (troposphere), last month was the hottest August on record. For 2016 to be colder than the previous hottest year (1998), the troposphere would have to average less than 0.19 °C for the remaining months.

In the lower troposphere (UAH beta v6.05) last month is the second hottest August on record, lower than it was in 1998. For 1998 to remain the hottest year in the UAH lower troposphere record, the average for the next four months would need to be below 0.32 °C.

Troposphere temperatures for July 2016

The troposphere temperatures are out for July 2016. The lower troposphere is recorded in UAH v6 beta 5 and RSS TLT v3.3. This report also covers RSS TTT for the troposphere (without the "lower"). This report follows pretty much the same format as previous monthly updates. It's my fault that it's a bit later than usual. (I was away most of last week.)

In all records, the July global anomaly was a bit higher than it was in June but lower than earlier this year as El Niño is now over. In the lower troposphere (UAH beta v6.05) last month is the second hottest July on record, lower than it was in 1998. For RSS TTT (troposphere), last month was the hottest July on record.

Troposphere temperature (RSS TTT v4) chart

First here is RSS TTT with the latest dataset, version 4. TTT seems to be measure more of the troposphere than TLT (that is, it has a greater vertical profile) with less of the stratosphere than the mid-troposphere data (TMT). It shows a higher rate of warming than RSS v3.3 and higher than UAH. Hover the cursor (arrow) over the plots to see the data points, trend etc.

The chart below is the average of the 12 months to July, from August 1979 to July 1980, through to August 2015 to July 2016.

Figure 1 | Troposphere temperature for 12 months to July (TTT). Anomaly is from the 1979-1998 mean. Data source: RSS

Troposphere temperatures for June 2016

The troposphere temperatures are out for June 2016. The lower troposphere is recorded in UAH v6 beta 5 and RSS TLT v3.3. This report also covers RSS TTT for the troposphere (without the "lower").

In all records, the June global anomaly dropped again, as El Nino dissipated. In the lower troposphere (UAH beta v6.05) and the troposphere (RSS TTT) the June anomaly is lower than it was in 1998. The drop was greater than most people expected, particularly for UAH TLT. Anthony Watts called it "spectacular". However it was still the second hottest June in the UAH record and the third hottest in RSS TTT.

Troposphere temperature (RSS TTT v4) chart

First here is RSS TTT with the latest dataset, version 4. TTT seems to be measure more of the troposphere than TLT (that is, it has a greater vertical profile) with less of the stratosphere than the mid-troposphere data (TMT). It shows a higher rate of warming than RSS v3.3 and higher than UAH.

Hover the cursor (arrow) over the plots to see the data points, trend etc.

The chart below is the average of the 12 months to June, from July 1979 to June 1980, through to July 2015 to June 2016.

Figure 1 | Troposphere temperature for 12 months to June (TTT). Anomaly is from the 1979-1998 mean. Data source: RSS

Troposphere temperatures for May 2016

The troposphere temperatures are out for May 2016. The lower troposphere as UAH v6 beta 5 and RSS TLT v3.3. As last month, this report also covers RSS TTT for the troposphere.

In all records, the May global anomaly dropped again, as El Nino dissipated. In the lower troposphere (UAH beta v6.05) and the troposphere (RSS TTT) the May anomaly is lower than it was in 1998.

Troposphere temperature (RSS TTT v4) chart

First here is RSS TTT with the latest dataset, version 4. TTT seems to be measure more of the troposphere than TLT (that is, it has a greater vertical profile) with less of the stratosphere than the mid-troposphere data (TMT). It shows a higher rate of warming than RSS v3.3 and higher than UAH.

Hover the cursor (arrow) over the plots to see the data points, trend etc.

The chart below is the average of the 12 months to May, from June 1979 to May 1980, through to June 2015 to May 2016.

Figure 1 | Troposphere temperature for 12 months to May (TTT). Anomaly is from the 1979-1998 mean. Data source: RSS

Troposphere temperatures for April and muttered excuses from deniers at WUWT

The troposphere temperatures are out for April 2016. The lower troposphere as UAH v6 beta 5 and RSS TLT v3.3. As last month, this report also covers RSS TTT for the troposphere.

In all records, the April global anomaly is lower than it was for February and March. In the lower troposphere (UAH and RSS TLT only) the April data is lower than it was in 1998. In RSS TTT, April is the hottest April in the record.

Troposphere temperature (RSS TTT v4) chart

Last month I posted the TTT data from RSS which is now at version 4. TTT seems to be more of the troposphere than TLT (that is, it has a greater vertical profile) with less of the stratosphere than the mid-troposphere data (TMT). Hover the cursor (arrow) over the plots to see the data points, trend etc.

The chart below is the average of the 12 months to April, from May 1979 to April 1980, through to May 2015 to April 2016. Some caution is warranted because months to the end of 2016 are likely to be cooler on average than the first months of this year (2016).

Figure 1 | Troposphere temperature for 12 months to April (TTT). Anomaly is from the 1979-1998 mean. Data source: RSS

About that tropical "hot spot"

A couple of days ago I wrote about the new paper by Steven Sherwood and Nidhi Nishant, which was reporting the release of an updated radiosonde dataset, and findings from an analysis of those data.

Data sources: Scripps and GISS/NASA

One of the things the authors reported was the "tropospheric hot spot" - though they didn't use that term in the paper itself (only the press release). I've never previously thoroughly looked into this myself. I knew about it in general terms, because some deniers point to what they regard as lack of evidence as evidence that global warming isn't happening. Which is really, really weird when you think about it. Or when you look at surface temperature data as in the chart on the right.

Anyway, I decided to go and learn more about this so-called "tropospheric hot spot".

Nine Denier 101 Techniques: Anthony Watts gets into a hot spot in the tropical troposphere

There's a new paper in ERL by Steven C Sherwood and Nidhi Nishant, which reports an updated version of their radiosonde dataset. It is probably going to cause quite a ruckus in the deniosphere. From the paper (my formatting):

Temperature trends in the updated data show three noteworthy features.

• First, tropical warming is equally strong over both the 1959–2012 and 1979–2012 periods, increasing smoothly and almost moist-adiabatically from the surface (where it is roughly 0.14 K/decade) to 300 hPa (where it is about 0.25 K/decade over both periods), a pattern very close to that in climate model predictions. This contradicts suggestions that atmospheric warming has slowed in recent decades or that it has not kept up with that at the surface.
• Second, as shown in previous studies, tropospheric warming does not reach quite as high in the tropics and subtropics as predicted in typical models.
• Third, cooling has slackened in the stratosphere such that linear trends since 1979 are about half as strong as reported earlier for shorter periods.

Wind trends over the period 1979–2012 confirm a strengthening, lifting and poleward shift of both subtropical westerly jets; the Northern one shows more displacement and the southern more intensification, but these details appear sensitive to the time period analysed. There is also a trend toward more easterly winds in the middle and upper troposphere of the deep tropics.

Radiosondes are instruments that are sent aloft in balloons, to take measurements in the atmosphere. (You might have seen Roy Spencer and John Christy combine measures from radiosondes with satellite tropospheric temperatures in their various unscientific attempts to befuddle the US government and readers of blogs.)