2018 has the fourth hottest May on record

Summary: May 2018 was the fourth hottest May on record. The 12 month period to May 2018 was the third hottest June to May period on record.

According to GISS NASA, the average global surface temperature anomaly for May was 0.82 °C, which is 0.09 °C less than the hottest - May 2016.

Below is a chart of the average of 12 months to May each year. The 12 months to May 2018 averaged 0.82 °C above the 1951-1980 mean, which was 0.19 °C cooler than the 12 months to May 2016.

This makes it the third hottest June to May 12 month period on record after 2016 and 2015.

Second hottest October on record, just above October 2016

Summary: October 2017 was the second hottest October on record. The 12 month period to October 2017 was the second hottest November to October period on record.

According to GISS NASA, the average global surface temperature anomaly for October was 0.90 °C, which is 0.18 °C less than the October 2015. October 2017 was just 0.01 °C hotter than the next hottest October in 2016.

Below is a chart of the average of 12 months to October each year. The 12 months to October 2017 averaged 0.90 °C above the 1951-1980 mean, which was 0.13 °C cooler than the 12 months to October 2016.

This makes it the second hottest September to October 12 month period on record.

August 2017 is the second hottest August on record - the #climate is changing

Summary: August 2017 was the second hottest August on record. The 12 months to August 2017 was the second hottest September to August period on record.

According to GISS NASA, the average global surface temperature anomaly for August was 0.85 °C, which is 0.14 °C less than the August 2016. August 2017 was 0.05 °C hotter than the next hottest August in 2014, which had an anomaly of 0.80 °C.

Below is a chart of the average of 12 months to August each year. The 12 months to August 2017 averaged 0.91 °C above the 1951-1980 mean, which was 0.13 °C cooler than the 12 months to August 2016.

This makes it the second hottest September to August 12 month period on record.

2017 has just had the hottest July on record!

Summary: July 2017 was the hottest July on record by just a smidgen. The 12 months to July 2017 was the second hottest August to July period on record.

Because July is the hottest month, it also makes it the hottest month ever on record. Edit: it's been pointed out to me that August last year pipped July 2016 and July 2017 as the hottest month on record.

According to GISS NASA, the average global surface temperature anomaly for July was 0.83 °C, which is 0.01 °C more than the July 2016, making July 2017 the hottest July in the record.

Below is a chart of the average of 12 months to July each year. The 12 months to July 2017 averaged 0.92 °C above the 1951-1980 mean, which was 0.11 °C cooler than the 12 months to July 2016.

This makes it the second hottest August to July 12 month period on record.

June is cooler in 2017 but still the 4th hottest June on record

Summary: June 2017 was the fourth hottest June on record. The 12 months to June 2017 was the second hottest July to June period on record.

According to GISS NASA, the average global surface temperature anomaly for June was 0.69 °C, which is 0.10 °C less than the hottest June in 2016, making June 2017 the fourth hottest June in the record. It's the hottest June in any year when there was no El Nino.

Below is a chart of the average of 12 months to June each year. The 12 months to June 2017 averaged 0.91 °C above the 1951-1980 mean, which was 0.10 °C cooler than the 12 months to June 2016.

This makes it the second hottest July to June 12 month period on record.

Second hottest May on record

According to GISS NASA, the average global surface temperature anomaly for May was 0.88 °C, which is 0.05 °C less than the hottest May in 2016, making May 2017 the second hottest May in the record.

Here is a chart of the average of 12 months to May each year. The 12 months to May 2017 averaged 0.91 °C above the 1951-1980 mean, which was 0.10 °C cooler than the 12 months to May 2016. This makes it the second hottest May to May 12 month period on record.

Figure 1 | Global mean surface temperature anomaly for the 12 months to May each year. The base period is 1951-1980. Data source: GISS NASA

(Google has just made some changes to its charting program, and has yet to iron out some of the kinks. Let me know if you see any problems. I am having trouble seeing the values to the right of the charts. Hopefully it will get fixed soon.)

Exploring South East Asian heat extremes of 2016 elicits silly comments from Anthony Watts

There's a new paper out in Nature Communications this week, in which the authors explore the factors affecting the extreme heat in south east Asia last year.  In mainland south east Asia, April 2016 was the warmest April on record, by a long way. It was 0.9 °C hotter than the previous hottest April (1998).

The paper opens with the following:

In April 2016, southeast Asia experienced surface air temperatures (SATs) that surpassed national records, exacerbated energy consumption, disrupted agriculture and caused severe human discomfort.

It seems a worthwhile research project, particularly with global warming likely to cause more disruption and discomfort like this over time.

[The figure at the top right is from the paper, and shows the relative contribution of El Niño (green bars) versus global warming (red bar) for the 15 hottest Aprils on record in mainland Southeast Asia. Click to enlarge it.]

Second hottest April on record

According to GISS NASA, the average global surface temperature anomaly for April was 0.88 °C, which is 0.18 °C lower than the hottest April in 2016, making April 2017 the second hottest April in the record.

Here is a chart of the average of 12 months to April each year. The 12 months to April 2017 averaged 0.91 °C above the 1951-1980 mean, which was 0.07 °C cooler than the 12 months to April 2016,. This makes it the second hottest April to April 12 month period on record.

Figure 1 | Global mean surface temperature anomaly for the 12 months to April each year. The base period is 1951-1980. Data source: GISS NASA

Second hottest March on record - NASA global temperature update with year to date comparison

According to GISS NASA, the average global surface temperature anomaly for March was 1.12 °C, which is 0.16 °C lower than the hottest March in 2016, making March 2017 the second hottest March in the record.

Here is a chart of the average of 12 months to March each year. The 12 months to March 2017 averaged 0.93 °C above the 1951-1980 mean and was almost identical to the 12 months to March 2016, being just 0.02 °C cooler. This makes it the second hottest April to March 12 month period on record.

Figure 1 | Global mean surface temperature anomaly for the 12 months to March each year. The base period is 1951-1980. Data source: GISS NASA

Second hottest February on record - is another El Niño on the way already?

According to GISS NASA, the average global surface temperature anomaly for February was 1.10 °C, which is 0.22 °C lower than the hottest February in 2016 and the second hottest February in the record.

Here is a chart of the average of 12 months to February each year. The 12 months to February 2017 averaged 0.94 °C above the 1951-1980 mean and was almost identical to the 12 months to February 2016, being just 0.01 °C hotter. This makes it the hottest March to February 12 month period on record.

Figure 1 | Global mean surface temperature anomaly for the 12 months to February each year. The base period is 1951-1980. Data source: GISS NASA

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.

Weather Reality Check: What a La Niña looks like...in pictures

The wacky conspiracy theorists at WUWT think that every nation who watches and warns about ENSO events, so that farmers and fishers can plan ahead, are hiding reality from deniers. They seem to think that it helps weather reporting agencies maintain the "climate hoax" conspiracy to say there's probably not going to be a La Niña this year after all, so that when the temperature plunges to new lows just short of an ice age in a few weeks (as deniers seem to think) ...well, I don't know what conspiracy theorists think the weather bureaux will do then ...

Losing his grip on ENSO: Bob Tisdale thinks he's an expert, and yet...

Bob Tisdale fancies himself as an ENSO expert, yet he doesn't show that in his WUWT article today (archived here). He's complaining that a couple of days ago NOAA removed the "watch" status for La Nina. Bob's headline was "NOAA Cancels La Niña Watch While La Niña Conditions Exist". Well, he seems to be the only person who thinks La Nina conditions exist. Oh, except maybe for Anthony Watts who, way back in June, declared that we are already having a La Nina.

Today Bob Tisdale wrote:

Regardless of the existing (and strengthening) La Niña conditions, NOAA has canceled its La Niña Watch, which had been in effect since April.

Except there are not conditions currently existing for La Nina. Bob's wrong. This is where he was wrong - almost everywhere:

1. Bob didn't base his assessment on the ENSO definition's standard of the ONI, which is a 3 month running mean;
2. He based his current sea surface temperature anomaly in the Nino 3.4 region on the wrong average baseline, making it appear approx 0.4 C colder than it is (the cutoff is -0.5 C) (h/t Rattus Norvegicus);
3. He used the wrong dataset (Reynolds OI v2), not the one used as standard for ENSO estimates (ERSST v4).

Summary added by Sou 4:57 pm 10 September 2016

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

Another "ice age" fear for England - only at WUWT

Anthony Watts has posted another alarmist article, this time about how England might suffer from an ice age some time soon. The guest opinion was penned by John Hardy (UK), and was posted under a painting by Abraham Hondius: “The Frozen Thames” 1677 (during the Maunder minimum) (archived here).

One of the important messages from this article is that one would be very unwise to pay any attention to anything written at WUWT. I don't know why deniers have such an aversion to learning about climate. Nor do I know why they are so shameless about showing their ignorance. Nor why they are apparently unwilling or unable to do basic fact-checking or research.

La Niña or no, nada?

Now that El Niño has shut down, people are wondering if a La Niña will develop this year. Anthony Watts has been egging it on. Way back in March, before the El Niño had finished, he was predicting a La Niña. Today he's quoting a report from NOAA from a couple of weeks ago (9 June), in which the prediction was 75% in favour of La Niña:

Overall, ENSO-neutral conditions are present and La Niña is favored to develop during the Northern Hemisphere summer 2016, with about a 75% chance of La Niña during the fall and winter 2016-17.

The Australian Bureau of Meteorology has been much more conservative, with all its forecasts so far being only 50:50 in favour of La Niña. In its latest ENSO wrap-up yesterday, BoM stated:

Recent observations and climate model forecasts continue to suggest La Niña may develop in the coming months, hence the Bureau’s ENSO Outlook remains at La Niña WATCH level. A La Niña WATCH means there is a 50% likelihood of La Niña developing during the second half of 2016.  If La Niña does develop, climate models suggest it is unlikely to reach levels seen in the most recent event of 2010–12, which was one of the strongest La Niña events on record.