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gerontocrat

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Re: Global Surface Air Temperatures
« Reply #1950 on: February 06, 2019, 08:30:19 PM »
The UK MetOffice says there is a 10% chance that a strong El Nino combined with continuing AGW will produce a burp of global temps above the 1.5 degrees c. in one year between now and 2023.

And that as the years progress that 10% will grow...

https://www.theguardian.com/environment/2019/feb/06/met-office-global-warming-could-exceed-1-point-5-c-in-five-years
Met Office: global warming could exceed 1.5C within five years
Lowest Paris agreement target may temporarily be surpassed for first time between now and 2023

Quote
Global warming could temporarily hit 1.5C above pre-industrial levels for the first time between now and 2023, according to a long-term forecast by the Met Office. Meteorologists said there was a 10% chance of a year in which the average temperature rise exceeds 1.5C, which is the lowest of the two Paris agreement targets set for the end of the century.

Until now, the hottest year on record was 2016, when the planet warmed 1.11C above pre-industrial levels, but the long-term trend is upward. Man-made greenhouse gases in the atmosphere are adding 0.2C of warming each decade but the incline of temperature charts is jagged due to natural variation: hotter El Niño years zig above the average, while cooler La Ninã years zag below. In the five-year forecast released on Wednesday, the Met Office highlights the first possibility of a natural El Niño combining with global warming to exceed the 1.5C mark.

Dr Doug Smith, Met Office research fellow, said: “A run of temperatures of 1C or above would increase the risk of a temporary excursion above the threshold of 1.5C above pre-industrial levels. Predictions now suggest around a 10% chance of at least one year between 2019 and 2023 temporarily exceeding 1.5C.”

Although it would be an outlier, scientists said the first appearance in their long-term forecasts of such a “temporary excursion” was worrying, particularly for regions that are usually hard hit by extreme weather related to El Niño. This includes western Australia, South America, south and west Africa, and the Indian monsoon belt.

They also noted that the probability of 1.5C years would steadily increase unless emissions were rapidly scaled back.
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Re: Global Surface Air Temperatures
« Reply #1951 on: February 07, 2019, 12:28:51 AM »
James Hansen, Makiko Sato, Reto Ruedy, Gavin A. Schmidt and Ken Lo (06 February 2019),
"Global Temperature in 2018 and Beyond"

http://www.columbia.edu/~jeh1/mailings/2019/20190206_Temperature2018.pdf

Abstract.Global surface temperature in 2018 was the 4th highest in the period of instrumental measurements in the Goddard Institute for Space Studies (GISS) analysis.  The 2018 global temperature was + 1.1°C (~2°F) warmer than in the 1880-1920 base period

The four warmest years in the GISS record are the past four years, 2015-2018.

(note: which mimics the last 4 years being the highest CO2 readings in the records too. )

The strong 2015-16 El Niño in the equatorial Pacific Ocean is more prominent in the annual 2015 map than in 2016, yet the impact of the El Niño on global temperature is greater in 2016.  This is a result of the lag of 3-4 months between El Niños and their effect on global temperature.

Global land area has warmed about twice as much as global ocean, as shown in Figure 3.  Linear fit to the period 1975-present yields a warming about 1.6°C over land and 08°C over ocean.

( note: the land is where most people live, have thier homes and businesses and farms )

Thus average warming of land is about 3°F .... The warming is reaching levels at which it becomes easier for the public to appreciate that the warming is significant

If a substantial El Niño develops, 2019 global temperature is expected to rise, although it is unlikely that the El Niño will approach the strength of the 2015-16 El Niño.

Continuing changes in global climate forcings also affect global temperature.  The record 2016 global temperature was abetted by its near coincidence with a solar maximum (Figure 6). 

Climate forcing by greenhouse gases (GHGs) is the dominant drive for climate change, because it is continually increasing, but changing solar irradiance is not a negligible factor.

It has been argued that the coming Solar Minimum could be prolonged with the irradiance declining below its range so far in the era of accurate satellite data, analogous to the Maunder Minimum of 1645-1715 (Eddy, 1976)4 when sunspots supposedly were almost absent.  The next few years of solar irradiance data may be particularly informative.


( In summary - it's hot and it's getting hotter fast! The primary cause, increasing human driven GHGs are continually increasing. It's not rocket science folks. )

BornFromTheVoid

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Re: Global Surface Air Temperatures
« Reply #1952 on: February 16, 2019, 01:03:57 PM »
JMA have January 2019 as the joint 2nd warmest on record (with 2017)



1st. 2016(+0.52°C),
2nd. 2019,2017(+0.39°C),
4th. 2015,2007,2002(+0.29°C)

https://ds.data.jma.go.jp/tcc/tcc/products/gwp/temp/jan_wld.html

rboyd

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Re: Global Surface Air Temperatures
« Reply #1953 on: February 16, 2019, 11:39:40 PM »
And we are at weak El Nino conditions at the moment with lower solar irradiance. Running out of excuses for the deniers.
« Last Edit: February 17, 2019, 12:21:46 AM by rboyd »

wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1954 on: February 17, 2019, 07:40:06 AM »
The running 12-months has briefly dropped below the 30-year linear trend on GISS-LOTI.  My guess is that it goes back above it in the next 2-3 months.  February is on track for high anomaly. BTW the 30-year linear trend is 0.19°C/decade. Only a matter of time before it goes above 0.20°C/decade.

crandles

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Re: Global Surface Air Temperatures
« Reply #1955 on: February 22, 2019, 10:17:33 PM »
Recent divergences continue



No, this isn't a denier graph. The conclusion reached include

Quote
This implies about -0.06 °C per decade combined cooling bias in HadCRUT4 over the last two decades. The trend in differences between CW-buoy and HadCRUT4 over 1997-2017 is -0.06 (±0.02) °C per decade. Note that coverage bias was more prominent up to about 2012, while the ship-buoy bias has come increasingly to the fore during the recent surge.

https://deepclimate.org/2019/02/22/2018-surface-temperature-update-part-1-recent-divergences-continue/

wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1956 on: March 06, 2019, 02:44:49 AM »
Surprised at no mention.  Massive jump in NCEP reanalysis dailies the last 2 weeks. February had the highest anomaly in nearly 2 years and March is off to a very warm start.  February may come close to +1.0°C for GISS-LOTI based on Moyhu site.

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Re: Global Surface Air Temperatures
« Reply #1957 on: March 19, 2019, 06:49:46 PM »
GISS came in at +0.92°C for February.  The running 12-month mean has just jogged below the 30-year linear trend of 0.19°C per decade.  With this year’s ENSO cycle it should head back above it pretty soon.

rboyd

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Re: Global Surface Air Temperatures
« Reply #1958 on: March 19, 2019, 08:31:08 PM »
We may not be hitting that trend line again.

b_lumenkraft

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Re: Global Surface Air Temperatures
« Reply #1959 on: March 29, 2019, 05:15:28 PM »
Global Warming Changes in Annual Average Temperature Distribution


Klondike Kat

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Re: Global Surface Air Temperatures
« Reply #1960 on: March 29, 2019, 06:21:36 PM »
We may not be hitting that trend line again.

Do you really believe that temperatures will not rise that much in the future?

miki

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Re: Global Surface Air Temperatures
« Reply #1961 on: March 29, 2019, 06:37:27 PM »
We may not be hitting that trend line again.

Do you really believe that temperatures will not rise that much in the future?

What he means, if I am correct, is that we may stay well above that trend line in the future. In other words, that trend line may well become a baseline (after we hit it again upward ;-)

Tor Bejnar

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Re: Global Surface Air Temperatures
« Reply #1962 on: March 29, 2019, 06:46:36 PM »
I shared Miki's interpretation, although when I read Klondike's question, I realized my interpretation was technically opposite what was written.  I wait with bated breath Rboyd's elucidation.
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oren

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Re: Global Surface Air Temperatures
« Reply #1963 on: March 29, 2019, 06:50:00 PM »
It's obvious rboyd meant we may not go as low as the trendline again.

Klondike Kat

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Re: Global Surface Air Temperatures
« Reply #1964 on: March 30, 2019, 12:51:42 AM »
Crandles,
The 0.06 difference is significant when you consider that the HadCRUT4 trend is 0.14 / decade.

rboyd

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Re: Global Surface Air Temperatures
« Reply #1965 on: March 30, 2019, 03:50:13 AM »
It's obvious rboyd meant we may not go as low as the trendline again.

That is what I meant, obviously.

jai mitchell

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Re: Global Surface Air Temperatures
« Reply #1966 on: March 31, 2019, 12:30:23 AM »
GISS came in at +0.92°C for February.  The running 12-month mean has just jogged below the 30-year linear trend of 0.19°C per decade.  With this year’s ENSO cycle it should head back above it pretty soon.

I agree and this means that for most of the period between 2015-2019 we will be above the trend.

I contend that this trend will continue, to greater degree and that this trend line will rise to 0.3C (or higher) per decade.  with recent the recent decade being at least 0.4C
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Tony Mcleod

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Re: Global Surface Air Temperatures
« Reply #1967 on: March 31, 2019, 10:38:58 AM »
Say good bye to that GISS trendline.



The last year or so of flat temps has had the denierati all excited about the coming "cooling". If only.

rboyd

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Re: Global Surface Air Temperatures
« Reply #1968 on: April 01, 2019, 01:19:50 AM »
Average growth per year ppm/ppb
           CO2E   CO2    CH4
1990s    2.4     1.5      5.3
2000s    2.7     2.0      2.9
2010s    3.6     2.4      7.5  (2011-2018 for CO2, 2011-2017 for CH4 and CO2E)

The growth in N2O has been pretty constant over these three decades, while CFC 11 and 12 peaked in 2000 and are on a slow long term decline. HFC 134a and HCFC 22 have been slowly growing. The CO2E number is from the NOAA AGGI. The yearly CO2E (AGGI) increase averaged 4 for the past three years. With CO2 and CH4 probably having increased above trend in 2018, the CO2E (AGGI) increase could be 5ppm. Could we hit 6ppm this year with the ENSO-related jump in CO2?

I think that the AGGI still uses 28 for the 100yr CO2 equivalency of CH4, so understates things versus the most up to date number (36?). If we take a 20-year view of CH4 (86-100 CO2 equivalent), then the actual increase in the earth energy imbalance is significantly greater. Makes sense why the temperature trend would be accelerating.

With the changes to ship fuel oil regulations to greatly reduce sulphate emissions, together with China's attempts to reduce sulphate emissions (scrubbers etc. more than any real coal use reductions), the trend may be exacerbated by reductions in the dimming effects going forward. Although India is trying hard to keep up the rate of dimming with its increases in coal usage.

https://www.esrl.noaa.gov/gmd/aggi/aggi.html
« Last Edit: April 01, 2019, 01:33:00 AM by rboyd »

wdmn

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Re: Global Surface Air Temperatures
« Reply #1969 on: April 13, 2019, 01:44:40 PM »
I know it's not this simple, for a number of reasons, but I decided to do some very rough calculations as a thought experiment on the idea of a "carbon budget."

Assumption: there's about a 15 year delay between emissions and when the increased radiative forcing from those emissions shows up in global temperature change. (I read this a few places, I'm not sure how accurate it is. I know that there are also much slower response times for ocean warming, and due to other feedbacks).

2017 GMSTA would include all of the warming caused from emissions up until the end of 2002.

The total emissions of CO2 from fossil fuel use and land use change from 1959 to 2003 were 1008.69 Gt.

According to NASA GISS data, GMSTA from 1974 to 2017 is roughly 1C. According to the 15 yr assumption, most of the warming in that period would be explained by the 1008.69 Gt of CO2 emissions.

In the 15 years between 2003-2017, global CO2 emissions were 565.41 Gt, which is roughly 56% of the emissions from the previous 43 years.

Shouldn't we expect that 15 years after 2017 (i.e 2032), we will see an additional 0.56C warming? That would bring us to approximately 1.75C warming since preindustrial (using NASA's figures).

oren

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Re: Global Surface Air Temperatures
« Reply #1970 on: April 13, 2019, 05:52:16 PM »
I seem to remember Ned W saying that emissions translate rather quickly into radiative forcing. Maybe one year.
Radiative forcing contributes to warming as long as there is a radiative imbalance. I'm not sure how long this takes, but certainly we have more warming in the pipeline even if GHG levels stabilize (and they won't anytime soon).

rboyd

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Re: Global Surface Air Temperatures
« Reply #1971 on: April 13, 2019, 07:22:31 PM »
In the past few years the trends of both warming (increased methane and CO2 levels) and cooling (switching from coal to natural gas cuts sulfate aerosols, same with low-sulfate ship fuel and scrubbers) are accelerating in the wrong direction - so an accelerated increase in temperatures would be expected.

Using the 20-year CO2 equivalent for methane delivers an overall CO2E for all GHG's of over 600ppm, net that out with the aerosol cooling effects and we may still be at a level of radiative forcing that is double that of pre-industrial times, and only just at the start of the accelerated trend in temperatures.

All government policies point to more of the same:
- Continued focus on fracking with Trump removing the regulations on methane leaks. The energy expended in liquefaction makes this even worse.
- Increased gas supplies from Russia, with its leaky old infrastructure and no methane leak regulations
- Stabilization to low growth in coal use, with increased use of scrubbers (use up in Asia and Africa, down in Europe and the USA)
- The ongoing replacement of high-sulfur transport fuels
- Rates of wind and solar growth that are not high enough to offset even half of overall energy growth

The end result may catch the global community very much by surprise in the next few years, maybe we get a crisis in 2021/2022 in time for the big UN FCCC meetings. Then we get an accelerated focus on geoengineering?

wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1972 on: April 16, 2019, 12:35:32 AM »
No major surprise but still a GISS +1.11°C March would’ve been a huge month prior to 2015-2016 Niño. Now mostly crickets.  NCEP reanalysis still has the dailies up high into April. Could see another +1.0° C month.

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Re: Global Surface Air Temperatures
« Reply #1973 on: April 16, 2019, 07:29:21 AM »
I know it's not this simple, for a number of reasons, but I decided to do some very rough calculations as a thought experiment on the idea of a "carbon budget."

Shouldn't we expect that 15 years after 2017 (i.e 2032), we will see an additional 0.56C warming? That would bring us to approximately 1.75C warming since preindustrial (using NASA's figures).

I tend to agree with you.

wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1974 on: April 16, 2019, 03:13:18 PM »
Running 12-month GISS-LOTI temperature is quickly heading back towards 30-year trend line.  Of course due to accelerating warming the 12-month running temperature never dropped below the 40, 50 or 60 year trend line.

Klondike Kat

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Re: Global Surface Air Temperatures
« Reply #1975 on: April 16, 2019, 05:35:28 PM »
True.  However, those trend lines are less steep.

jai mitchell

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Re: Global Surface Air Temperatures
« Reply #1976 on: April 16, 2019, 07:16:59 PM »
FWIW
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Re: Global Surface Air Temperatures
« Reply #1977 on: April 16, 2019, 09:14:46 PM »
This fits the "accelerating climate sensitivity" concept, the hotter it gets the higher the climate sensitivity. Also fits with the concepts of feedbacks kicking in, one after the other, as temperature rises.

wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1978 on: April 17, 2019, 12:55:38 AM »
True.  However, those trend lines are less steep.

That’s the point. A more apples to apples comparison would have been overlapping 30-year trend lines. The trend is a derivative, the steepening of the trend lines is the 2nd derivative: acceleration.

Tom_Mazanec

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Re: Global Surface Air Temperatures
« Reply #1979 on: April 19, 2019, 04:22:23 AM »
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wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1980 on: April 19, 2019, 05:17:42 PM »
Here's your overlapping 30-year trends of the last 50 years. Overlap is every 10 years.  Rounding up the trends are: 0.16°C per decade, 0.17°C per decade & the most recent 30 years is 0.20°C per decade.

wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1981 on: May 02, 2019, 05:35:18 PM »
GISS-LOTI should come in around +1.00°C for April.  Reanalysis has done a good job with the ramp up in global mean temps for February & March.  Moyhu's analysis converts to ~+1.02°C on GISS for April. 

wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1982 on: May 17, 2019, 02:42:12 PM »
GISS-LOTI came in at +0.99°C for April.  2nd warmest April on record behind of course April 2016. 

Something I continue to highlight is that the drop off after the 2015-2016 super Niño was much less than previous Niño's: 2010, 1998, etc.

The running 12-month mean anomaly is now back up to the linear trend of 0.20°C per decade.  It took post 1998 & 2010 much longer to rebound.

El Cid

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Re: Global Surface Air Temperatures
« Reply #1983 on: May 17, 2019, 03:14:31 PM »

Something I continue to highlight is that the drop off after the 2015-2016 super Niño was much less than previous Niño's: 2010, 1998, etc.



Actually, looking at your chart, the drop off after 2010 was smaller (a bit more than 0,1 C) and after 1998 was about the same (somewhat more than 0,2 C) as after 2016 (cca 0,2 C).

It is your green line that is obviously misplaced as it seems that the trend is not linear in nature.

So the problem is not with the dropoff (as it is absolutely similar to previous ones), but with the trend


b_lumenkraft

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Re: Global Surface Air Temperatures
« Reply #1984 on: May 17, 2019, 03:18:35 PM »
... meaning with the next El Niño we might 'upgrade' into the 1,5˚ realm?

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Re: Global Surface Air Temperatures
« Reply #1985 on: May 17, 2019, 05:16:13 PM »
... meaning with the next El Niño we might 'upgrade' into the 1,5˚ realm?

I think our ,UK, Met office has already said that 1.5C will be breached by 2023 i.e. when the next Nino comes through?
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Re: Global Surface Air Temperatures
« Reply #1986 on: May 17, 2019, 05:35:36 PM »
GISS-LOTI came in at +0.99°C for April.  2nd warmest April on record behind of course April 2016. 

Something I continue to highlight is that the drop off after the 2015-2016 super Niño was much less than previous Niño's: 2010, 1998, etc.

The running 12-month mean anomaly is now back up to the linear trend of 0.20°C per decade.  It took post 1998 & 2010 much longer to rebound.
I've been playing with your graph - adding lines. I sure hope the last line added - the short red one, is not the shape of things to come.
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Re: Global Surface Air Temperatures
« Reply #1987 on: May 17, 2019, 05:57:25 PM »
Everything linear might be too optimistic...

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Re: Global Surface Air Temperatures
« Reply #1988 on: May 17, 2019, 06:11:23 PM »
GISS-LOTI came in at +0.99°C for April.  2nd warmest April on record behind of course April 2016. 

Something I continue to highlight is that the drop off after the 2015-2016 super Niño was much less than previous Niño's: 2010, 1998, etc.

The running 12-month mean anomaly is now back up to the linear trend of 0.20°C per decade.  It took post 1998 & 2010 much longer to rebound.
I've been playing with your graph - adding lines. I sure hope the last line added - the short red one, is not the shape of things to come.

I hope not also.  I think the rest of your lines are likely to extend into the future - at least the short term.

wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1989 on: May 17, 2019, 06:13:27 PM »

[/quote]

Actually, looking at your chart, the drop off after 2010 was smaller (a bit more than 0,1 C) and after 1998 was about the same (somewhat more than 0,2 C) as after 2016 (cca 0,2 C).

It is your green line that is obviously misplaced as it seems that the trend is not linear in nature.

So the problem is not with the dropoff (as it is absolutely similar to previous ones), but with the trend
[/quote]

You're right about 2010.  A better way to phrase it would be the spike above or below the 30-year linear trend(green line).  The 2 years of La Niña/cool ENSO barely dropped GISS below the linear trend in 2017 & 2018.  Post 1998 & 2010 the drop below the linear trend was more pronounced.

Klondike Kat

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Re: Global Surface Air Temperatures
« Reply #1990 on: May 17, 2019, 08:05:30 PM »


Actually, looking at your chart, the drop off after 2010 was smaller (a bit more than 0,1 C) and after 1998 was about the same (somewhat more than 0,2 C) as after 2016 (cca 0,2 C).

It is your green line that is obviously misplaced as it seems that the trend is not linear in nature.

So the problem is not with the dropoff (as it is absolutely similar to previous ones), but with the trend
[/quote]

You're right about 2010.  A better way to phrase it would be the spike above or below the 30-year linear trend(green line).  The 2 years of La Niña/cool ENSO barely dropped GISS below the linear trend in 2017 & 2018.  Post 1998 & 2010 the drop below the linear trend was more pronounced.
[/quote]

That may be a premature conclusion.  Look at the drop after the 1972/3 El Nino. 

oren

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Re: Global Surface Air Temperatures
« Reply #1991 on: May 17, 2019, 08:49:35 PM »
After 1998 the dropoff came to the previous peaks of the 90s. After 2016 the dropoff came nowhere near the previous peaks of the 2010s.

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Re: Global Surface Air Temperatures
« Reply #1992 on: May 17, 2019, 09:09:06 PM »
After 1998 the dropoff came to the previous peaks of the 90s. After 2016 the dropoff came nowhere near the previous peaks of the 2010s.

because the trend line is a curve up, and not a straight line, IMO.

Rich

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Re: Global Surface Air Temperatures
« Reply #1993 on: May 17, 2019, 09:36:32 PM »
When I see the increased slope of the temperature line in recent years, my first thought is that coal use from declined from 2014-16. Perhaps the increase in slope is due to a reduction in aerosols?

Ken Feldman

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Re: Global Surface Air Temperatures
« Reply #1994 on: May 18, 2019, 12:47:14 AM »
When I see the increased slope of the temperature line in recent years, my first thought is that coal use from declined from 2014-16. Perhaps the increase in slope is due to a reduction in aerosols?

Unfortunately, there has been increased demand for natural gas to offset the coal decline and transportation, mainly oil, has increased.  So while the trend for coal is going in the right direction, overall, fossil fuel use hasn't peaked yet.

And here's a graph showing the greenhouse gas forcings:



Here it is in terms of radiative forcing:



So while decreased aerosols may have played a role, the increased emissions of greenhouse gases are still the bigger issue.


wolfpack513

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Re: Global Surface Air Temperatures
« Reply #1995 on: May 19, 2019, 12:17:20 AM »
If you're worried about end points using a linear trend I've added another 30-year linear regression ending in 2001.

3 years after the end of the 1997-1998 Niño is of course 2001.  You'll notice still below the linear regression.  3 years after 2016, GISS is back up to the 30-year linear regression.
« Last Edit: May 19, 2019, 12:22:23 AM by wolfpack513 »

Darvince

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Re: Global Surface Air Temperatures
« Reply #1996 on: May 19, 2019, 01:58:32 PM »
Here all all lines wolfpack513 mentioned. The main difference I see is not the fall from the Niño temperatures but rather the far larger rise that occured in 2014-16 and began even before the Niño started, in 2014.