Global Surface Air Temperatures

[Yuha]

Add NOAA & BEST to the list of July 2019 as warmest on record.  GISS should be there too once it's released.  BEST came in at +0.84°C above the 1950-1981 baseline.  A fairly large margin over the previous record: July 2016 +0.72°C.

GISS (V4) came in at +0.93°C, clearly warmer than the +0.85°C of July 2016.

https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt

[DrTskoul]

Global Warming: How Fast?

Interesting graphs by Tamino.

So what can we say about Earth’s warming rate right now? Based on the smoothed model, I’d say it’s almost surely between 1.66 and 2.67 deg.C/century. The average rate from 1970 to now was between 1.70 and 1.95 deg.C/century. Note that the values from the straight-line model are well within the uncertainty range of the smoothed model, so we don’t have statistically significant evidence of any recent change in the warming rate since 1970. It’s certainly possible, we just don’t have solid evidence for it.
My opinion: the present warming rate is about 2.23 deg.C/century, but could be as low as 1.66 or 2.67. It might be substantially higher than its average-since-1970 value of 1.83, but then again it might not.

My other opinion: given that the uncertainty is so large, we should at least be prepared for the possibility that right now, Earth is warming substantially faster than it has for the last 50 years. If that’s true, it’s a matter of serious concern.

[wolfpack513]

Touching more on the acceleration of the last 50 years.  Here's BEST 1970-2019 with overlapping 30-year trends.  Each 30-year rate has been increasing starting with 1970-1999.  In order here's the rates: 1.60°C/century, 1.80°C/century & 2.00°C/century.

[Tom_Mazanec]

Touching more on the acceleration of the last 50 years.  Here's BEST 1970-2019 with overlapping 30-year trends.  Each 30-year rate has been increasing starting with 1970-1999.  In order here's the rates: 1.60°C/century, 1.80°C/century & 2.00°C/century.

So the acceleration is 0.2 per decade?

[dnem]

No. The trends would be 0.16, 0.18 and .20 per decade for the overlapping 30 year periods. That's 0.02 deg C/decade.

[oren]

Touching more on the acceleration of the last 50 years.  Here's BEST 1970-2019 with overlapping 30-year trends.  Each 30-year rate has been increasing starting with 1970-1999.  In order here's the rates: 1.60°C/century, 1.80°C/century & 2.00°C/century.

So the acceleration is 0.2 per decade?

Acceleration units must have /t^2.
In this case it's 0.2C/century/decade.

[dnem]

So the acceleration is 0.2 per decade?

Acceleration units must have /t^2.
In this case it's 0.2C/century/decade.


Which I think would imply a 10% growth rate in the rate of increase, per decade, yes? Something like this:
Decade   Rise
2020           0.20
2030           0.22
2040          0.24
2050           0.27
2060           0.29
2070           0.32
2080           0.35
2090           0.39
2100           0.43

So, starting somewhat arbitrarily at 1.0 C over "baseline", and applying a 0.2 C/decade increase, increasing at 10% per decade, would give a temperature rise of something like this:

[jlessard80]

That 3.5 degrees, plus the 1.0 or so degrees of warming so far, matches up pretty well with the "business as usual"

"Under RCP 8.5, the world’s average temperature would rise by 4.9 degrees Celsius"

https://www.theatlantic.com/science/archive/2019/01/rcp-85-the-climate-change-disaster-scenario/579700/

[Tom_Mazanec]

Touching more on the acceleration of the last 50 years.  Here's BEST 1970-2019 with overlapping 30-year trends.  Each 30-year rate has been increasing starting with 1970-1999.  In order here's the rates: 1.60°C/century, 1.80°C/century & 2.00°C/century.

So the acceleration is 0.2 per decade?

Acceleration units must have /t^2.
In this case it's 0.2C/century/decade.

AAARGH!
You’re right of course.

[dnem]

Personally, I'd be surprised if the second derivative (I hope I have that right!) of temperature didn't continue to increase.  The only thing that might slow down the rate of increase of the rate of increase would be a drastic, long-lasting  slowdown in the global economy (which will come before long).  But that might unleash a bout of aerosol-reduction heating.

[KiwiGriff]

Acceleration should be expressed as  0.02C decade²

[Gray-Wolf]

So where do the 'well represented' ? ( in the paleo record?) 'Step ups' in global temps fit into all of this?

Where do the 'unique' responses that a 'warming' (at such a rate?) must bring? (Black Swan Events?)

Surely it's not about "How we are progressing" but " How we 'could' progress?"

Do we need to be 'hair triggered' for the first signs if an 'unexpected uptick' in rate of global temps?

Or do we know from past global experiences of such GHG increases, over such a short period, to feel 'self assured' that we got this?

[nanning]

^^

If I'm correct, before the Anthropocene, never have GHG so massively increased over such a short period, 75 years.
Uncharted territory.

[wolfpack513]

Reanalysis from Moyhu's site is on track for 2nd warmest August on GISS.  2016's +1.02°C is likely out of reach(we'll see).  Moyhu's latest reanalysis version hit July on the dot.  Through the 24th of August reanalyses is at +0.95°C GISS equivalent.  http://www.moyhu.org.s3.amazonaws.com/data/freq/ncep.html

[wolfpack513]

Global datasets are starting to come down for August 2019.  NOAA came in at +0.92°C which ties for 2nd warmest August.  YTD 2019 is at 3rd warmest behind 2016 & 2017. 

In 2017 September-December tails off as 2015 soars.  So 2019 could finish 2nd warmest year or 2015 may pass 2019 through December & this year finishes 3rd warmest.

**GISS-LOTI** came down right after this.  +0.90°C.  2nd warmest (alone) on NASA's dataset.

[BornFromTheVoid]

3rd warmest August according to the JMA: https://ds.data.jma.go.jp/tcc/tcc/products/gwp/temp/aug_wld.html



Warmest summer overall: https://ds.data.jma.go.jp/tcc/tcc/products/gwp/temp/sum_wld.html

[nanning]

I like those graphs BornFromTheVoid, they have the base line, clear axis names, units and a zero point .
The only thing that's missing is the delta_T from pre-industrial to the base line 1981-2010. But hardly anyone puts that in.

[wolfpack513]

I like those graphs BornFromTheVoid, they have the base line, clear axis names, units and a zero point .
The only thing that's missing is the delta_T from pre-industrial to the base line 1981-2010. But hardly anyone puts that in.

Except that JMA use's a linear trend for a non-linear dataset.  The current rate of warming is more than double the 1890-2019 rate.  Very misleading to have that 0.70°C/Century on the chart.

[nanning]

Thanks for the info and correction wolfpack513 .

[wolfpack513]

Thanks Nanning!    

Take Berkeley Earth global mean temperature for example.  The 20-year running average clearly shows steady warming since the 1970s which is much different than warming rates the prior 120 years.  The current warming rate of 2°C/century is 3 times that of the linear trend since 1850.

[gerontocrat]

Hot from the Press:- I really think you need to read it..... (my comments in italic)
Lots more in it on consequences etc.

https://library.wmo.int/doc_num.php?explnum_id=9936
The Global Climate in 2015–2019 from the World Meteorological Organisation


Air Temperatures

The average global temperature for 2015–2019, which is currently estimated to be 1.1 ± 0.1 °C above pre-industrial (1850–1900) level, is therefore likely to be the warmest of any equivalent period on record. It is 0.20 ± 0.08 °C warmer than the average for 2011–2015.

That's a rate of 0.4 °C per decade. Hansen was right?

The global mean land-surface air temperature for 2015–2019 was approximately 1.7 °C above pre-industrial and 0.3 °C warmer than 2011–2015.

That's a rate of 0.6 °C per decade

The global mean sea-surface temperature for 2015–2019 was approximately 0.8  °C above pre-industrial and 0.13 °C warmer than 2011–2015.

That's a rate of 0.26 °C per decade

Sea Level Rise

Over the five-year period 2014–2019, the rate of global mean sea-level rise has amounted to 5 mm/year. This is substantially faster than the average rate since 1993 of 3.2 mm/year. The observed rate of global mean sea-level rise has increased from 3.04 mm/year during the 10-year period 1997–2006 to 4.36 mm/year during the previous 10-year period 2007–2016

Ocean heat content

Ocean heat content has reached new records since 2015. Measured over the layer from the surface to 700 meters depth, 2018 had the largest ocean heat content values on record, with 2017 ranking second and 2015 third. 2016 also had higher values than any pre-2015 year in most datasets. In the NCEI dataset, the ocean heat content anomaly (recomputed relative to the reference period 1981–2010) for 2018 was 13.0 x 1022 J for the 0–700 meter layer, and 18.2 x 1022 J for the 0–2000 meter layer, compared with the pre-2015 annual records of 9.5 x 1022 J and 14.3 x 1022 J, respectively.

SEAWATER IS BECOMING MORE ACID
 

Observations from open ocean sources over the last 20 to 30 years have shown a clear trend of decreasing average pH, caused by increased concentrations of CO2  in seawater.  There has been an overall increase in acidity of 26% since the beginning of the industrial revolution.

It is well established that this decreases the effectiveness of the ocean CO2 sink

[TerryM]

^^
So - 1.5 C by 2030, unless things continue to speed up?


That's going to take some amazing mitigation. Thank god we've such wonderful politicians to lead us through these perilous times.
Terry

[bbr2314]

The running five-year anomaly belies the recent cooling trend NW of the blob. Jan-Mar and Apr-Jun 2019 are below. The data is not dishonest since it is technically valid but I do not think it accurately reflects the current state of things as the snowfall anomalies have begun rolling positively in tandem with the worsening sea ice deficits.

[wolfpack513]

Using a 5-year average?  Deniers do the same thing.  Be careful with cherry picking, it goes both ways.  Only 18 ONIs (ENSO) were at or below 0.0°C in the last 5 years.  2011-2015 there were 33 ONIs below 0.0°C.

20-year smooths is about as low as I like to go due to internal climate variability.  Still gives you about +1.2°C on BEST.  At current pace that's just under 15 years before +1.5°C

[gerontocrat]

^^
So - 1.5 C by 2030, unless things continue to speed up?


That's going to take some amazing mitigation. Thank god we've such wonderful politicians to lead us through these perilous times.
Terry

The Uk Metoffice reckoned there might be a year or two of +1.5 in the 2020's - outliers due to temporary climatic conditions

[TerryM]

^^
Gerontocrat, it seems as though we've run out of time to do much more than hunker down and face what's coming.


I haven't been overly impressed by our progress to date - your charts made things all too clear. We've had opportunities to cooperate but found more profit in competition. We could have legislated against mining exporting, or shipping coal, but we relied on "market forces" - forces totally divorced from any thought of survival.
Plans for initiating mitigation that begin decades after the crisis weren't just useless, they froze out other schemes that could have been initiated soon enough to have had some effect.


Nuclear power has always had it's dangers. Germany's sudden pull back necessitated increasing her reliance on coal, oil, and gas - then America slowed Germany's access to relatively clean Russian gas in hopes of replacing it with much dirtier LNG shipped across an ocean. Poland welcomed her transition to home grown coal - while the EU did nothing, even as the EU chides others for ignoring their Paris Accord commitments.


I'm not forgetting my own heavily hypocritical Canada. We recognized the necessity, most even had some sense of the urgency. We voted out the deniers, then our new "progressive" government opted to shore up the dirtiest oil producing scheme on the planet. We're a rich country that wouldn't have been brought to ruin by shutting down the tar sands, but we hadn't the political will to do the one meaningful thing we could have done as a country.


Russia isn't the enemy & neither is China. This isn't an attack by "others", this is a suicide pact that our representatives, and theirs, signed in all of our names.
Terry

[vox_mundi]

The World Just Had Another Month of Record Heat
https://earther.gizmodo.com/the-world-just-had-another-month-of-record-heat-1838771974

New data released by the Copernicus Climate Change Service (C3S), the European Union’s climate agency, shows that last month tied for the hottest September on record. This adds to the stunning string of record or near-record heat the world has been dealing with since June and underscores the growing severity of the climate crisis.

The data released on Friday reveals that this past September was 1.2 degrees Celsius (2.2 degrees Fahrenheit) above the pre-industrial average. It was also 0.57 degrees Celsius (1 degree Fahrenheit) above the average September measured from 1981 to 2010, putting it “virtually on par” with September 2016

https://climate.copernicus.eu/surface-air-temperature-september-2019

[rboyd]

The World Just Had Another Month of Record Heat
https://earther.gizmodo.com/the-world-just-had-another-month-of-record-heat-1838771974

The data released on Friday reveals that this past September was 1.2 degrees Celsius (2.2 degrees Fahrenheit) above the pre-industrial average. It was also 0.57 degrees Celsius (1 degree Fahrenheit) above the average September measured from 1981 to 2010, putting it “virtually on par” with September 2016

That means that we recovered from the post El Nino drop in just 3 years with a not very high Nino 3.4 anomaly. At the same time we have the growth in atmospheric CO2 concentrations in the high 2.5+ppm/yr range. Certainly not very comforting statistics.

[bluice]

That means that we recovered from the post El Nino drop in just 3 years with a not very high Nino 3.4 anomaly. At the same time we have the growth in atmospheric CO2 concentrations in the high 2.5+ppm/yr range. Certainly not very comforting statistics.

Well, you are certainly not overstating it

The big question is if post-2016 warming is caused by some kind of natural variability pushing up the rate of heating. If it isn't, we are truly and thoroughly screwed, unless there will be an overlooked negative feedback or perhaps a random cooling event.

[El Cid]

Global temps between 2013-18 vs 2003-8 are up 0,23 C, which is pretty much the same as 2003-2008 vs 1993-1998 (0,22 C) - no accelaration there.
(NASA, giss - temp data).

We will likely see 0,5 C/ decade on NH midlatitude land for at least 2-3 decades in my view

[BornFromTheVoid]

2nd warmest September on record according to the JMA
https://ds.data.jma.go.jp/tcc/tcc/products/gwp/temp/sep_wld.html



8 warmest Septembers all in the last 8 years.

[wolfpack513]

Berkeley Earth came in at warmest September on record.  Of course GISS, JMA & NOAA were just below 2016.

For me the trends are more interesting than individual months.  Here's overlapping 30-year Berkeley Earth trends.  1970-1999: 0.17°C per decade, 1980-2009: 0.18°C per decade & 1990-2019: 0.20°C decade. 

[wolfpack513]

NCEP Reanalysis came in very warm for October.  Conversion to GISS is looking like >+1.00°C for October 2019.  October GISS record is +1.08°C in 2015. 

[rboyd]

We seem to be blowing away that post-Nino global temperature drop in a hurry, while at the same time year over year global CO2 atmospheric concentration growth is staying above 2.5ppm (and over 9.5ppb for methane).

And another 3 years before we get the next IPCC report in 2022 and people possibly wake up to this new reality.

[El Cid]

....

And another 3 years before we get the next IPCC report in 2022 and people possibly wake up to this new reality.

LOL. People don't give a shit about the IPCC report. People care about what they themselves actually feel. If we have 2-3 more very dry and hot summers in Europe, people will vote for the Green parties in herds.

[anthropocene]

Copernicus has October 2019 as warmest October (only by 0.01degC over 2016 October).

https://climate.copernicus.eu/surface-air-temperature-october-2019

[Tom_Mazanec]

El CID:
That is one reason the US is so deep in denial. It has had the least warming of just about any land area, and actually has had, if anything, more snow.

[Lewis]

Copernicus has October 2019 as warmest October (only by 0.01degC over 2016 October).

https://climate.copernicus.eu/surface-air-temperature-october-2019

2015 I believe you meant?

[Klondike Kat]

El CID:
That is one reason the US is so deep in denial. It has had the least warming of just about any land area, and actually has had, if anything, more snow.

So true.  No only that, but temperatures in the U.S. have moderated overall, with increased winter low temperatures and decreased summer high temperatures.  Hence, it is part denial and part approval for the better weather.

[El Cid]

El CID:
That is one reason the US is so deep in denial. It has had the least warming of just about any land area, and actually has had, if anything, more snow.

i also agree 100%

[anthropocene]

El CID:
That is one reason the US is so deep in denial. It has had the least warming of just about any land area, and actually has had, if anything, more snow.

So true.  No only that, but temperatures in the U.S. have moderated overall, with increased winter low temperatures and decreased summer high temperatures.  Hence, it is part denial and part approval for the better weather.

I wish you'd stop posting these falsehoods. Summer high temperatures may have increased more slowly than winter lows but they're still increasing (from 1960s) - this is not the same as decreasing. The dustbowl anomaly causing the unusual spike of 1930s and particulates warp results from before the 1960s. Unlike the dustbowl, the current increase in maximums is here to stay and will only get worse. And how many people can remember the 1930s or even 1960s? For most people maximum temps have been going up most of their lives.

https://science2017.globalchange.gov/chapter/6/

[anthropocene]

Copernicus has October 2019 as warmest October (only by 0.01degC over 2016 October).

https://climate.copernicus.eu/surface-air-temperature-october-2019

2015 I believe you meant?

Yes 2015 - thanks for the correction.

[Klondike Kat]

El CID:
That is one reason the US is so deep in denial. It has had the least warming of just about any land area, and actually has had, if anything, more snow.

So true.  No only that, but temperatures in the U.S. have moderated overall, with increased winter low temperatures and decreased summer high temperatures.  Hence, it is part denial and part approval for the better weather.

I wish you'd stop posting these falsehoods. Summer high temperatures may have increased more slowly than winter lows but they're still increasing (from 1960s) - this is not the same as decreasing. The dustbowl anomaly causing the unusual spike of 1930s and particulates warp results from before the 1960s. Unlike the dustbowl, the current increase in maximums is here to stay and will only get worse. And how many people can remember the 1930s or even 1960s? For most people maximum temps have been going up most of their lives.

https://science2017.globalchange.gov/chapter/6/

Have you read you reference?  Winter low temperatures have increased an average of 5F since 1900, and everywhere except for a few sections of the southeast.  The coldest days have increased an average of 3.3F, highest in the North and lowest in the Southeast.  Summer high temperatures have not changed since 1900, with the hottest days decreasing an average of 0.9F.   Every section of the country experienced a decrease, except for the southwest.

The heat wave index (Fig 5.4) is not just lower than the dust bowl era of the 1930s, but every decade from 1910 through the 50s.  An increase in the heat wave index, warm spells, and warmest daily temperatures is only detectable when compared to the low values of the 1960s.  Cherry-picking the 1960s as your start date to validate your claim does very little to improve your stance or reputation.

[blumenkraft]

Kat, you are cherrypicking again. Global temperatures are rising. You know that!

[El Cid]

Kat, you are cherrypicking again. Global temperatures are rising. You know that!

PLS, put it into context. We were talking about the fact, that the US population does not really feel adverse effects of climate change as opposed to eg Germany, and that is why most of the population (again, as opposed to Germany, or more broadly Europe) does not feel the need to act.

Plain and simple: people act when they themselves feel the change not because the IPCC or anyone else says so.

Europe experienced some very strange summers (hot and dry) and that directly led to much more popular support for green parties. Again, as opposed to the US.

See attached chart of very hot summers in Central and Western) Europe vs the US

[El Cid]

Another chart. The last 4 summers were extremely hot with records in Europe while they were somewhat warmer than average with no significant records in the US. So Europeans are more willing to believe global warming than Americans since they experience it very much

[Klondike Kat]

Kat, you are cherrypicking again. Global temperatures are rising. You know that!

Read the posts by El Cid to understand the discussion at hand.  Extraneous comments are not helpful.

[ArcticMelt2]

https://www.noaa.gov/news/october-2019-was-coolest-in-10-years-as-us-continued-its-wettest-year-to-date

October 2019 was coolest in 10 years as U.S. continued its wettest year to date

[anthropocene]

El CID:
That is one reason the US is so deep in denial. It has had the least warming of just about any land area, and actually has had, if anything, more snow.

So true.  No only that, but temperatures in the U.S. have moderated overall, with increased winter low temperatures and decreased summer high temperatures.  Hence, it is part denial and part approval for the better weather.

And later: "Cherry-picking the 1960s as your start date to validate your claim does very little to improve your stance or reputation."

1) Have you read the article? The 1960s is mentioned because that date is explicitly stated in the link. That is the time when the impacts of (one-off) drivers of USA temperature decreased allowing the (global) heating trend take the dominant role. It also happens to be a period that includes the life experience of the majority of people. Since we are discussing what is experienced by Americans, using the 1960s as a starting point seems to make perfect sense.

2) I'm not denying that temperature increases have been variable (in location and time) and that the experience of temp. increase may be less bad (and even good in some cases) for Americans compared to other regions of the globe. You are quite welcome to argue those points.

3) Would you like to state what time period the statement "but temperatures in the U.S. have moderated overall" covers? Moderated suggests change and the wording of the sentence suggests the end of the period is now. So when are you saying this period of moderation started?

[Klondike Kat]

El CID:
That is one reason the US is so deep in denial. It has had the least warming of just about any land area, and actually has had, if anything, more snow.

So true.  No only that, but temperatures in the U.S. have moderated overall, with increased winter low temperatures and decreased summer high temperatures.  Hence, it is part denial and part approval for the better weather.

And later: "Cherry-picking the 1960s as your start date to validate your claim does very little to improve your stance or reputation."

1) Have you read the article? The 1960s is mentioned because that date is explicitly stated in the link. That is the time when the impacts of (one-off) drivers of USA temperature decreased allowing the (global) heating trend take the dominant role. It also happens to be a period that includes the life experience of the majority of people. Since we are discussing what is experienced by Americans, using the 1960s as a starting point seems to make perfect sense.

2) I'm not denying that temperature increases have been variable (in location and time) and that the experience of temp. increase may be less bad (and even good in some cases) for Americans compared to other regions of the globe. You are quite welcome to argue those points.

3) Would you like to state what time period the statement "but temperatures in the U.S. have moderated overall" covers? Moderated suggests change and the wording of the sentence suggests the end of the period is now. So when are you saying this period of moderation started?

1)  The 1960s is but one of the dates mentioned, and it is mentioned simply as the time that temperatures bottomed, without regards to one-off impacts.  Yes, there has been an increase since the 1960s, but there is also a decrease since the 1930s, and no overall change since the start of the 20th century.

2)  No argument on those points.

3)  The timeframe is that given in the link, namely comparing present day temperatures to a 1901-1960 baseline.  The coldest temperatures have increased ~3F on average over that timeframe, and in every region of the country.  The hottest temperatures have decreased by 1F, and has occurred in every region except the southwest.  Yes, moderated implies change - particulary change towards less extreme, and the end of the period is now, as suggested.