The last 10 years are the hottest ever, yet deniers are still in denial

Summary: Despite three years of La Nina, 2022 was the sixth hottest year on record. The last decade was the hottest decade on record.

As you all know by now, we're causing the world to heat up. We've not got to a stage where we've stabilised the global temperature. In fact, we seem to be nowhere near stabilisation. Yet strangely there are still a few global warming deniers floating about. These deniers are arguing once again that an ice age is coming, or it's started cooling, or global warming has stopped, or "CO2 warming is a hoax" or some such nonsense. It's prompted me to write another article about how global temperature has been changing.

According to GISS NASA, the average global surface temperature anomaly for 2022 was 0.89 °C. This is 0.13°C below the hottest year so far. The hottest was 2020 at 1.02°C above the 1951 to 1980 average.

Below is a chart of the average of 12 months to December each year.

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

As you may know, each of the five decades since 1972-1981 has been hotter than the previous one. The chart below shows how the world has been heating up since early last century. The chart includes a dotted line showing the mean annual temperature for the 20th century. Let's see what next year brings, especially if there is another El Nino.

Figure 2 | Global mean surface temperature anomaly in ten year blocks. The base period is 1951-1980. Data source: GISS NASA

I've also included a chart grouped by averages over 20 year periods showing how the rate of warming increased quite a bit over the latest 20 year period. 

Figure 3 | Global mean surface temperature anomaly by 20 year periods. The base period is 1951-1980. Data source: GISS NASA

It's the increase in greenhouse gas that's causing warming!

Climate disinformers still exist, would you believe. Even after all the weather disasters of the past twenty years or so, there are still people who spread lies for various reasons. 

Peter Sinclair has talked about this on Climate Denial Crock of the Week. Apparently one of the "paid to disinform" brigade is running about shouting "CO2 warming is a hoax". It's no longer hard to believe that even Elon Musk has been spreading denial on Twitter, which he seems to have bought (for $44bn, mind you) mainly to promote the spread of harmful lies and neo-fascist propaganda. (It's changed from being social media to becoming his personal anti-social blog).

Anyway, about that junk science claim. To support his latest greenhouse gas denial, Milloy claims there has been cooling for the last eight years, since 2015. He wrote: "Per NOAA data, we have emitted ~450 billion tons of CO2 since 2015 (14% of total manmade atmospheric CO2) yet the planet has cooled."

The claim of cooling from 2015 is obviously nonsensical cherry-picking, which plenty of other people have pointed out. The average temperature for the past 8 years from 2015 to 2022 inclusive is 0.93°C above the 1951 to 1980 mean. The last 8 years has seen the biggest single increase of all, a whopping 0.27C. Before that, the biggest 8 year increase was 0.17C in the period 1999 to 2006 inclusive.

Here's a chart showing the rise in global temperatures to 2022, in eight year blocks.

Figure 4 | Global mean surface temperature anomaly in 8 year blocks. The base period is 1951-1980. Data source: GISS NASA

That's not all. Milloy, who tweets as @junkscience (which is what it is), wimped out on a prediction. He obviously couldn't bring himself to make an ice age cometh claim. That would be too silly, even for him. Instead he predicted that if there was an El Nino this year the global temperature would rise. Duh! He added that when it finished the temperature would "steady/slightly decline (again) as El Nino ebbs". That's not as certain, but the odds are that will happen, too.

However! Notice that Milloy doesn't mention the last three years of La Nina, which has a cooling effect on temperature - if all else is equal, which it isn't!

To show his cherry pick more clearly. The first chart shows the period Milloy is using for his false claim that greenhouse gases don't keep the earth warm.  As you can see, Milloy used the old, tired denier ploy of starting with two years of El Nino (hot years), and finishing in the third year of La Nina (slighly less hot years).

Figure 5 | Mean surface temperature anomalies from 2015 to 2022 from the 1951-1980 mean. Blue columns are La Nina years and orange columns and El Nino years. Data sources: GISS NASA and Bureau of Meteorology, Australia.

The second chart shows it in context of 50 years of warming. Each  

Figure 6 | Mean surface temperature anomalies from 1973 to 2022 from the 1951-1980 mean. Blue columns are La Nina years and orange columns and El Nino years. Data sources: GISS NASA and Bureau of Meteorology, Australia.

Now what the sharp-eyed and even the less eagle-eyed among you may notice is the El Nino years are getting hotter and the La Nina years are also getting hotter. It's not ENSO that's causing global warming. It's the greenhouse gas we're putting into the atmosphere, a large portion of which are all the waste products from the fossil fuels we're burning.

Incidentally, instead of starting at the two hottest El Nino years (2015 and 2016), if Milloy had included just one more year (2014) let alone any other previous years, his very slight decline in trend would have been an increase!

Cold blasts of hot air from the past

Here's a reminder of denier desperation and how disinformers have been feeding the deluded with false claims of "it hasn't warmed since" since, well, certainly since I've been blogging. In June 2013 I pointed out the absurdity when Anthony Watts' denier blog, WattsUpWithThat claimed it hadn't warmed since 1980, which was ridiculously wrong at the time, and it's warmed a lot more since then. Moving from the absurd to the more absurd, in October 2017 denier Anthony Watts crowed "it hasn't warmed since 2016". (2016 was a very hot El Nino year, yet 2020 was even hotter and there wasn't an El Nino that year.)

Where was it hot in 2022?

Last year was again hot almost everywhere. On the charts below as the legend shows, blue is for below the 1951-1980 average, and yellow/orange/red is above. Move the arrow at the left to the right to compare 2022 with 2020, which was the hottest year on record (so far). The cooler Pacific region of La Nina is clearly visible on the 2022 map.

Figure 7 | Maps showing mean surface temperature anomalies for 2022 and 2020 from the 1951-1980 mean. Data source: GISS NASA