Summary: The degree of global warming during the next few years might have large political effects, as the public policy debate appears to be at a critical point in its 29th year (from Hansen’s Senate testimony). Will the pause resume, or will we get rapid warming? Close examination of the monthly data will give us clues about this important question.
How can we see the short-term temperature trend?
There is no one true way to show trends in global temperature. Here are three different perspectives; all give roughly similar results. First, let’s look at a graph by NOAA of the global average surface temperature (their excellent interactive website shows data since the reliable instrument era began in 1880). The time period selected depends on what we are looking for. The following graph shows January’s. It minimizes the overall warming trend, which is concentrated in the months of May, June, & July. Click to enlarge.
The warming since 1950 — the period in which over half of the warming comes from anthropogenic causes — occurred almost entirely in two steps: 1981-83 (near the 1979-83 El Niño period) and 1998-99 (near the 1997-98 El Niño). Since then climate scientists have shown that the two century-long temperature rise has “paused” (aka the “hiatus”). There are various theories about the cause. Then came the spike of the 2015-2016 El Niño. The peak to peak rise, 1998 to 2016, was only 0.4°F.
What happens next? The El Niño might have been just a spike, after which temperatures will fall back to the 1998-2014 average — and the “pause” continues. If temperatures don’t fall back to their previous levels, then we begin a new watch. Will the 2015-16 El Niño start another stair step, with temperatures flat at a new high level? Or will temperatures begin a steady rise? The one month anomalies provide an easy if rough way to see which of these three scenarios unfolds, each having different political implications. Unfortunately, climate models cannot yet make reliable predictions for five to ten years horizons
NOAA: Global surface temperatures for January.
Purpose line added for the 1998-2014 average: the “pause”.
After the El Niño, some skeptics predicted a strong La Niña that would drop temperatures back to the levels of the pause. The major models correctly predicted that would not happen; there was only a brief weak La Niña. Starting in September, temperatures have been dropping slightly on a year-over-year basis — down 0.18°C YoY in January. It is too soon to draw any conclusions.
Satellites provide a second perspective.
For a second perspective, see the lower troposphere temperatures recorded by satellites (prepared for NASA by U AL-Huntsville). The below graph is by UAH lead scientists Roy Spencer. It tells a roughly similar story. Showing the full time series (not just January’s) gives more detail than the above graph — with more noise. It shows an El Nino spike in 2015-16, followed by a large, fast drop. Will it return to the previous plateau, start a new plateau, or begin steady growth? Click to enlarge.
The oceans give the best perspective.
In 2003 Roger Pielke Sr. said that the best measure of global warming is the total heat content of the world’s oceans (OHC). He was called a “denier”. Now ocean heat content (OHC) is the third measure of warming commonly used by climate scientists. NOAA posts this graph of annual OHC, showing the temperature anomaly vs. the reference period 1955-2006. The trend since 1970 is only 0.04°F per decade, slower than the surface atmosphere trend of 0.31°F). OHC is little affected by the weather, and clearly shows the warming trend since 1970.
Vital background about the temperature record.
“It is extremely likely (95 – 100% certain) that human activities caused more than half of the observed increase in global mean surface temperature from 1951 to 2010.”
— One of the most important conclusions of IPCC’s AR5 Working Group I.
This statement about past warming is important. But for making public policy decisions future warming we need to know the odds of various amounts of warming during the 21st century. There is no easy answer to this, let alone a consensus of climate scientists about it. So climate activists either ignore the research (such as the 4 scenarios described in AR5) or focus on the worst of these (the truly horrific RCP8.5) while ignoring its unlikely assumptions.
So far the weather has sided with the skeptics, with little of the extreme weather activists predicted. No surge of hurricanes after Katrina (despite the predictions). No sign of the methane monster. Northern hemisphere snow extent has risen since in both the Fall and the Winter. There is little evidence that we have passed one of the often declared “tipping points”.
So it is logical that — despite the efforts of government agencies, academia, and many ngo’s — the public’s policy priorities have been unaffected by the warming campaign (details here). Republican control of the Presidency, Congress, and most States makes policy action almost impossible for the next 4 years (ceteris paribus). As a result, activists are going thru the 5 stages of grief for their campaign.
Why do global temperatures rise erratically as CO2 steadily increases?
“Nonlinearities, feedbacks and critical thresholds within the Earth’s climate system” by José A. Rial et al, in Climatic Change, July 2004.
“The Earth’s climate system is highly nonlinear: inputs and outputs are not proportional, change is often episodic and abrupt, rather than slow and gradual, and multiple equilibria are the norm. While this is widely accepted, there is a relatively poor understanding of the different types of nonlinearities, how they manifest under various conditions, and whether they reflect a climate system driven by astronomical forcings, by internal feedbacks, or by a combination of both. …”
Update: new paper addresses this exact question
“Reconciling the signal and noise of atmospheric warming on decadal timescales” by Roger N. Jones and James H. Ricketts in Earth Systems Dynamics, 16 March 2017 — Abstract (red emphasis added)…
“Interactions between externally forced and internally generated climate variations on decadal timescales is a major determinant of changing climate risk. Severe testing is applied to observed global and regional surface and satellite temperatures and modelled surface temperatures to determine whether these interactions are independent, as in the traditional signal-to-noise model, or whether they interact, resulting in step-like warming. The multistep bivariate test is used to detect step changes in temperature data. The resulting data are then subject to six tests designed to distinguish between the two statistical hypotheses, hstep and htrend.
- “Test 1: since the mid-20th century, most observed warming has taken place in four events: in 1979/80 and 1997/98 at the global scale, 1988/89 in the Northern Hemisphere and 1968–70 in the Southern Hemisphere. Temperature is more step-like than trend-like on a regional basis. Satellite temperature is more step-like than surface temperature. Warming from internal trends is less than 40 % of the total for four of five global records tested …
- “Test 2: correlations between step-change frequency in observations and models (1880–2005) are 0.32 (CMIP3) and 0.34 (CMIP5). For the period 1950–2005, grouping selected events (1963/64, 1968–70, 1976/77, 1979/80, 1987/88 and 1996–98), the correlation increases to 0.78.
- “Test 3: steps and shifts (steps minus internal trends) from a 107-member climate model ensemble (2006–2095) explain total warming and equilibrium climate sensitivity better than internal trends.
- “Test 4: in three regions tested, the change between stationary and non-stationary temperatures is step-like and attributable to external forcing.
- “Test 5: step-like changes are also present in tide gauge observations, rainfall, ocean heat content and related variables.
- “Test 6: across a selection of tests, a simple stepladder model better represents the internal structures of warming than a simple trend, providing strong evidence that the climate system is exhibiting complex system behaviour on decadal timescales. This model indicates that in situ warming of the atmosphere does not occur; instead, a store-and-release mechanism from the ocean to the atmosphere is proposed. It is physically plausible and theoretically sound.
“The presence of step-like – rather than gradual – warming is important information for characterising and managing future climate risk.”
For More Information
If you liked this post, like us on Facebook and follow us on Twitter. For more information about this vital issue see the keys to understanding climate change and these posts about the politics of climate change…
- Important: climate scientists can restart the climate change debate – & win.
- How we broke the climate change debates. Lessons learned for the future.
- A story of the climate change debate. How it ran; why it failed.
- Science into agitprop: “Climate Change Is Strangling Our Oceans”.
- Ignoring science to convince the public that we’re doomed by climate change.
- Put the stories about record 2016 warming in a useful context.
To learn more about the state of climate change…
… see The Rightful Place of Science: Disasters and Climate Change by Roger Pielke Jr. (Prof of Environmental Studies at U of CO-Boulder, and Director of their Center for Science and Technology Policy Research). From the publisher…
“In recent years the media, politicians, and activists have popularized the notion that climate change has made disasters worse. But what does the science actually say? Roger Pielke, Jr. takes a close look at the work of the Intergovernmental Panel on Climate Change, the underlying scientific research, and the data to give you the latest science on disasters and climate change. What he finds may surprise you and raise questions about the role of science in political debates.”
40 thoughts on “A look at the future of global warming. Our political response depends on its trend.”
Reblogged this on Utopia – you are standing in it!.
Larry, the following seems to both confirm and contradict your analysis, the latter by repeating the frequently reported “news” that 15 of the hottest 16 years on record have occurred since 2000.
What point do you think they are missing? Thanks.
“This marks the fourth time in the 21st century a new record high annual temperature has been set (along with 2005, 2010, and 2014) and also marks the 39th consecutive year (since 1977) that the annual temperature has been above the 20th century average. To date, including 2015, 15 of the 16 warmest years on record have occurred during the 21st century. 1998 is currently tied with 2009 as the sixth warmest year on record.
“Overall, the global annual temperature has increased at an average rate of 0.07°C (0.13°F) per decade since 1880 and at an average rate of 0.17°C (0.31°F) per decade since 1970.
Sixteen Warmest Years (1880–2015)
The following table lists the global combined land and ocean annually-averaged temperature rank and anomaly for each of the 16 (two tied at #15) warmest years on record.
1 = WARMEST
PERIOD OF RECORD: 1880–2015 YEAR ANOMALY °C ANOMALY °F
1 2015 0.90 1.62
2 2014 0.74 1.33
3 2010 0.70 1.26
4 2013 0.66 1.19
5 2005 0.65 1.17
6 (tie) 1998 0.63 1.13
6 (tie) 2009 0.63 1.13
8 2012 0.62 1.12
9 (tie) 2003 0.61 1.10
9 (tie) 2006 0.61 1.10
9 (tie) 2007 0.61 1.10
12 2002 0.60 1.08
13 (tie) 2004 0.57 1.03
13 (tie) 2011 0.57 1.03
15 (tie) 2001 0.54 0.97
15 (tie) 2008 0.54 0.97
“Much of the record warmth for the globe can be attributed to record warmth in the global oceans. The annually-averaged temperature for ocean surfaces around the world was 0.74°C (1.33°F) higher than the 20th century average, easily breaking the previous record of 2014 by 0.11°C (0.20°F). Ocean temperatures for the year started with the first three months each third warmest for their respective months, followed by record high monthly temperatures for the remainder of the year as one of the stongest El Niños in the historical record evolved.
“Prior to 2015, the highest monthly anomaly on record for the global oceans was 0.74°C (1.33°F) above the 20th century average, occurring just last year in September 2014. This all-time monthly record was broken in August 2015 (+0.78°C / +1.40°F), then broken again in September (+0.83°C / +1.49°F), and then broken once more in October (0.86°C / 1.55°F)—making three all-time new monthly high global ocean temperature records set in a single calendar year. [Three all-time records (at the time) were also broken in 2014.] In 2015, the last four months of the year were more than 0.80°C higher than their respective average, the first instances in which this monthly-average threshold has been crossed.
“The warmth was due to the near-record strong El Niño that developed during the Northern Hemisphere spring in the eastern and central equatorial Pacific Ocean and to large regions of record warm and much warmer-than-average sea surface temperatures in parts of every major ocean basin.”
Please keep your comments brief. Dumping a 500 word copy & paste kills the thread. Be polite. Just summarize it and give the link. People can click on it to read it.
“the following seems to both confirm and contradict your analysis, the latter by repeating the frequently reported “news” that 15 of the hottest 16 years on record have occurred since 2000.”
How does it contradict what I said? You post 500 words and don’t bother to state that. The meaning of a “stairstep” is that on average everything on the top step will be above the datapoints before it. The high natural volatility of temperatures will produce occasional new record highs. Some will be statistically significant. Some won’t be — 2016 was 0.07°F warmer than 2015. But the actual 2016 anomaly was 1.69°F ±0.27°F, hence the “record” was less than the error bar.
Also — Of those 4 record highs, two were from the recent El Nino spike (2014, 2015). If you read the post — or even looked at the graphs I gave — you would see that I spent some time saying that this El Nino period lifted global temp out of the pause. That was the point of the opening section.
The last three paragraphs of your copy & past are irrelevant. If you are going to copy & paste, please limit it to pertinent text. “Much of the record warmth for the globe can be attributed to record warmth in the global oceans.” etc, etc — where the warmth was is not the subject here.
Why so defensive? I copied a section at length in an attempt to make the basis for my question to you more user-friendly. You are free to edit or delete at your pleasure. I read your post above and many others on this subject. I was hoping you could succinctly provide a response to lay people why a scientific consensus exists that a “pause” in global warming has taken place since the late 90s when NOAA–and the popular press have reported–the 15 hottest years on record have occurred since 2000, based on surface temperatures. You also pointed out that ocean temps have not shown such a pause, and stated that “the oceans give the best perspective.”
Is that more on point?
Thank you. That is an excellent comment. Brief and clear. Great questions.
(1) “provide a response to lay people why a scientific consensus exists that a “pause” in global warming has taken place since the late 90s”
Because many peer-reviewed papers say so, including reports from the major climate agencies. Here is a sample of 80+ (title, summary, links).
(2) “since the late 90s when NOAA–and the popular press have reported–the 15 hottest years on record have occurred since 2000”
That is the meaning of a “pause” (as the term is used) — the average temperature for a period is flattish (change roughly same as margin of error, or far slower than the long-term trend). As I said, when you stand on the top stair then you are above the other stairs.
(3) “You also pointed out that ocean temps have not shown such a pause, and stated that “the oceans give the best perspective.”
As I said, oceans heat slowly. It’s the best perspective in the sense that it focuses on the long-term trend. However, as I said at the start of this post, the political response to climate change is driven (for good or ill) by short-term weather — which is the subject of this post.
“You are free to edit or delete at your pleasure.”
That’s a second issue. I neither edit or delete comments (except spam). I push for good comments — not discussion-killing long copy & paste that lack specific points. The alternative is what many (perhaps most) similar websites do: moderate comments so that most critical ones don’t appear — and ban people. Brad Delong and many liberal websites do that aggressively.
There are no easy solutions. See the page about the FM website’s comment policy, and read the large collection of quotes describing how other websites cope.
Also FYI, in case you have not seen this yet: “Humans Are Changing the Climate 170x Faster Than Natural Forces” https://futurism.com/humans-are-changing-the-climate-170x-faster-than-natural-forces/
Researchers behind the ‘Anthropocene equation’ report that climate change driven by humans on Earth far exceeds that of natural events spread across millennia. Attaching a specific number to demonstrate how much humans are affecting the climate in such a short time frame clearly shows the impact we have on the environment.
A NEW EQUATION
Scientists have devised a new mathematical equation that allows them to determine just how much humans are affecting the climate. According to the researchers, global temperatures have decreased by an average of 0.01 Celsius per century over the last 7,000 years. This figure is what they considered the baseline rate. In the last 45 years however, trends show that it has increased at 1.7 Celsius per century, due to greenhouse gas emissions.
In the paper, published in the journal The Anthropocene Review, the researchers go on to explain that across billions of years, Earth’s climate has been dependent on astronomical and geophysical forces, as well as internal dynamics of the planet. In the equation, these natural forces tend to zero because of how slow they affect the Earth’s climate, in contrast to human activity. In short, while these factors still affect Earth’s climate, human activity overtakes it significantly. This change represents a climate shift driven by humans that is 170 times faster than those caused by natural forces.
“We are not saying the astronomical forces of our solar system or geological processes have disappeared, but in terms of their impact in such a short period of time they are now negligible compared with our own influence,” co-author of the paper Will Steffen said.
“While it would seem imprudent to ignore the huge body of evidence pointing to profound risks, it comes at a challenging time geopolitically, when both fact-based world views and even international cooperation are questioned. Nowhere has this been clearer than in the US in recent weeks,” adds co-author of the study Owen Gaffney.
The relevance of this equation is two-fold. First it manages to clearly illustrate our current predicament. Attaching a specific number to demonstrate how much humans are affecting the climate in such a short time frame (in contrast to natural forces, which took millions and millions of years), clearly shows the impact we have on the environment.
“Crystallising this evidence in the form of a simple equation gives the current situation a clarity that the wealth of data often dilutes,” notes Steffen.
Second, it could also help drive action—given that we only have a small window to address the damage we have caused. As they explain in their paper, “the human magnitude of climate change looks more like a meteorite strike than a gradual change.” Earth may have shown remarkable resilience, but human societies aren’t likely to do as well.
“In the last 45 years however, trends show that it has increased at 1.7 Celsius per century, due to greenhouse gas emissions.” While I can completely buy the validity of what this sentence says, from what I know of the topic, it is an extremely lousy way to phrase it.
I don’t understand the point of a lot of this material you’re quoting, unless it is an effort to preach the gospel to the guys in the comments section on WUWT who more-or-less worship CO2 as their god, as best as I can tell. If it is to yell at Donald Trump, they will have to get in line. Yes, I acknowledge that human impact on global climate change is substantial and is the largest driver, certainly for the last 50 years and likely for longer. It is not that it is wrong; it is that it is facile, I guess. So what do we DO, now that our awareness is raised? (Fortunately, renewable energy is well on its way.)
Yes, you are a copy and paste star. Please stop. You copied and pasted a thousand words to a 1500 word post. Worse, most of this is not relevant to the post.
“Also FYI, in case you have not seen this yet”
Yes, I have been reading about this in Science and Nature for a year or so. I wrote a post about it, and have written several score posts about various aspects of this (e.g., 22 posts about the global catastrophe taking place in the oceans).
The newspapers have covered this quite extensively. But it has nothing whatsoever to do with the subject of this post.
Again, I was just sharing information. If you were already aware of this, and have previously written about it, that’s wonderful. And again, you are free to edit or delete at your pleasure. But why not just provide a succinct response that states you are aware of this and why you regard it is irrelevant, rather than simply asserting it is without explaining why?
For example, how can an ostensibly new way to measure global warming not be relevant to a post about global warming? You often repeat many of the same points and many of the same sources in your series of posts on this subject. I assume you do so at least in part so your readers do not have to go back and re-read or memorize your previous posts, but feel free to tell me if this is an erroneous assumption on my part. That would strike me as more informative than simply dismissing my comment as irrelevant on its face.
I’ve read your article about how the weather will decide who wins, one way or another. I think this will probably hold true if there was another major weather disaster that could be semi-plausibly blamed on climate shifts etc., though I doubt the rhetoric would change a great deal.
It’s a little bleak to think that even with all the growth in renewables and energy storage, the electric cars, all that other good stuff, we will be in the hands of what stuff we’ve emitted already for quite some time. At least it doesn’t seem to be causing large-scale disruption of agriculture yet, at least that I’ve heard. Hopefully it’ll stay that way!
Also this. Good news? http://www.eurasiareview.com/10022017-robert-reich-a-good-idea-even-if-its-from-republicans-oped/#.WKTbelUF4wo.facebook
“A group of former Republican officials (including James A. Baker, Henry Paulson, George P. Shultz, Marty Feldstein and Greg Mankiw) is proposing a carbon tax starting the tax at $40 per ton, that would gradually increase. The proceeds of the tax would be distributed to every American. The average family of four would receive $2,000 annually in dividends. As the tax rises, so would their dividends.
“Since everyone would receive the same amount of revenue from the tax regardless of their income level, the dividend would make a bigger difference for poorer families than for wealthier ones. It’s a win-win: Less carbon in the atmosphere, and more equal distribution of income.
“That it’s being proposed by Republicans doesn’t make the idea any less worthy. I’m aware that some on the left would rather use revenues from such a tax to invest in clean energy and other social causes rather than return the revenues directly to the public. That detail can be worked out. The idea is getting a hearing in the White House. And in these dreadful times, that’s good news indeed.”
That’s the second comment of zero relevance to this post. Any more and future comments will be moderated, with relevant comments going up. This isn’t your private news wire, where you post whatever you find interesting. It’s a comment thread about a specific post.
Apparently, relevance is relative. Quoting your intro–“Summary: The degree of global warming during the next few years might have large political effects, as the public policy debate appears to be at a critical point in its 29th year (from Hansen’s Senate testimony). Will the pause resume, or will we get rapid warming? Close examination of the monthly data will give us clues about this important question.”
You also said the following: “For making public policy decisions (about) future warming, we need to know the odds of various amounts of warming during the 21st century. There is no easy answer to this, let alone a consensus of climate scientists about it….Republican control of the Presidency, Congress, and most States makes policy action almost impossible for the next 4 years (ceteris paribus).”
I think much public policy affecting the future is probabilistic in nature, and often based on assumptions less certain than odds-making, which is obviously far from an exact science. So in light of your comments above, can you explain why you regard a Republican proposal for a carbon tax and dividend program as “irrelevant”, rather than once again simply dismissing it on its face as such?
“can you explain why you regard a Republican proposal for a carbon tax and dividend program as “irrelevant”, rather than once again simply dismissing it on its face as such?”
This is not a post about climate change — which is a complex subject, large beyond imagining. Posts on the FM website examine specific aspects of this issue. The summary clearly states its subject.
You could write a million words about possible public policy responses to climate change. That’s not the topic here.
“Apparently, relevance is relative”
No, I don’t believe that is correct with respect to your comment.
Thanks so much for gathering all this good data.
Trying to distill some points:
1. From 1970:
a. The average sea temperature is rising at 0.04 deg F/decade,
b. The surface atmosphere – 0.31
c. The low surface – not given (do you have it?), but from eyeballing Spencer chart looks similar – say ~0,3
2. Extrapolating linearly to 2050, the surface should warm ~1 deg F by 2050.
3. Since the atmospheric CO2 concentration increases, it will be somewhat higher – how much? needs to be reviewed.
Each of the monthly reports discusses a different aspect of the warming. The previous one discussed the trends in more detail. The bottom line: “The trend of warming is 0.25°F per decade since 1950, the era dominated by anthropogenic warming.”
“Extrapolating linearly to 2050”
Im 1987 I gave a presentation to the senior management of Schwab The President, Larry Stupski (now deceased), replied to my forecasts by saying “there are no straight lines in the real world.” He was, of course, correct. Conditions are always changing.
We’re seeing such a change now, as coal consumption declines in most of the world — replaced by natural gas and renewables. Esp significant is solar, whose costs are falling rapidly.
“Since the atmospheric CO2 concentration increases, it will be somewhat higher – how much? needs to be reviewed.”
Yes, that’s the key point. The massive global industrialization of 1945-2000 was a one-time event. The big events now in progress are different, and the CO2 trend will change.
Again, thank for your attention and investment.Very much appreciated. I am learning a lot.
1. For now I am staying on 1970, unless we have the corresponding 3 values (slopes) since 1950. Shouldn’t be hard.
2. No straight lines – acceleration. As explained, we expect acceleration in all three measures. It is hard for me to see it in the temperature charts starting 1970. Acceleration CAN clearly be seen on the oceanic chart (as shown from 1955). Which is in correlation to 3 as follows.
3. C02 concentration is rising (of course accelerating). It will continue to rise in the next 20 years (if not century). Willing to place a bet on the 20 years. What do you say? ;-)
“the CO2 trend will change”. At what year would you estimate it will be lower than todays ~400 PPM? I would say several decades at best. Until then I don’t expect the temp. slope to start slowing down.
4.Indeed local and temporal anomalies (like when EN happens) are greater. Anecdotally, in Boston where I live it is 76 deg right now. The highest value in record is 70 (http://bit.ly/2kV0tH2).
If anyone disagrees with a point, please help me and guide to the data that support your statement. Thanks for your kindness.
Thermalization and the Maxwell-Boltzmann velocity distribution of gas molecules explain why CO2 has no significant effect on climate. A potentially larger threat to humanity than failing to recognize that CO2 has no significant effect on climate is failing to realize what actually does. Beware the still-rising water vapor. Its increasing influence is addressed at http://globalclimatedrivers2.blogspot.com
(1) Rise in CO2 levels: “No straight lines – acceleration.”
You’re the one who said “linear”.
(2) “we expect acceleration in all three measures.”
Why? Who is “we”?
(3) “Acceleration CAN clearly be seen on the oceanic chart”
The ocean heat chart is a lagging indicator to atmospheric heating. The ocean depths warm slowly.
(4) “It will continue to rise in the next 20 years (if not century).”
I see no basis for that claim. The massive industrialization of the world from 194-2010 was a one-time event (the remaining underdeveloped areas are a small part of global population). Also, the conversion from coal has just begun. Looking further, the cost of solar has reached grid parity (narrowly defined) — a historic milestone (its the basis for acceleration in usage).
Further out in the 21st century we’ll probably have new energy sources. Private capital is funding fusion (e.g., Tri Alpha Energy). These people require hard evidence before investing, and they don’t have long time horizons.
(5) “if anyone disagrees with a point”
Scientists tend to see only slowly see changed economic patterns. So far they have focused on the IPCC’s worst-case scenario (doomsday RCP8.5). But that’s changing. Papers are appearing that do not rely on (or even mention) RCP8.5, shifting to the “mitigation scenarios” (i.e., slowing of CO2 emissions) Such as this new paper, looking at the RCP4.5 scenario (AR5’s 2nd best of 4 scenarios). NOAA press release: “Climate change to shift global pattern of mild weather.” See the paper: “Shifting patterns of mild weather in response to projected radiative forcing” by Karin van der Wiel et. al in Climate Change, January 2017.
If we’re now shifting to track RCP6.0 or even RCP4.5, we could be at RCP2.6 by mid-century. Under RCP2.6 we have negative GHG emissions in the second half of the 21st C.
(6) “If anyone disagrees with a point, please help me and guide to the data that support your statement.”
The RCP scenarios depend on assumptions of things we cannot reliably predict. They’re not based on “data”. Population growth, geopolitical events, tech change, economic growth. People have a poor record of predicting these for 10 years ahead. Your confidence in your long-term projections is …odd. Few scientists share your self-confidence.
I think CO2 levels are certainly going to be higher in the future, but the rate of increase is going to go down quite a bit, and may well end up net-negative once the population trends start inclining downwards or if and when we do really start shifting majorly away from fossil fuels. Even in the rosiest scenarios we’ll still be burning them when I’m old – just much, much less than some projections! And a situation where things inch up 1 ppm every few years, on average, due to defrosting vegetation in Siberia or bad weather over rainforests, is much better than most alternatives.
I also believe, though I forget the name of it, that there’s a diminishing return on how much warming would likely come about from a given unit of CO2. I’m also leaving aside the question of the possible effects of afforestation/reforestation or carbon capture technology – for all we know the people of 2050 will be 3D printing buildings out of megadiamond from atmospheric CO2.
Dan, extraordinary claims require extraordinary evidence. Ordovician Earth, some 450M years ago, was very different. Other variables such as continent locations played part. Indeed physics was the same. CO2 had GHG effect like today.
What are you attempting to say in that comment?
Are you willing to place a bet? $100 of today’s value, handed 20 years from now.
My bet will be that C02 level 20 years from now will be higher than today.
I assume your position is the opposite.
What do you say.
I’m a financial advisor. Betting is my business. I don’t bet on guesses about things that cannot be predicted. You get better odds at Vegas, where they also have pretty girls serving free drinks.
In my reply to Dan, I meant he is wrong when he wrote “CO2 has no significant effect on climate”. Have nothing more to say on that thread.
Thanks for the clarification!
Edge – The preponderance of evidence (I list several) is that CO2 has no significant effect on climate. About the only way to prove a negative is to prove a positive with which the negative cannot coexist. The analysis, which shows a match with measured temperatures, (98% 1895-2015) is certainly compelling.
Combine this with the facts it has never been proven CO2 has a significant effect on climate and that predictions assuming CO2 influence exhibit abysmal failure. https://judithcurry.com/2015/12/17/climate-models-versus-climate-reality/
Dear Dan, FM declined my bet. Perhaps you will agree.
I’ll bet that the next 10 years will be hotter in average than the past 10 years. I assume your position is opposite. $100.
What say you?
“that predictions assuming CO2 influence exhibit abysmal failure”
No, they don’t. That article by Pat Michaels and Chip Knappenberger gives a silly graph, misleading in several senses..
(1) It shows an average of model runs rather than the distribution of runs.
(2) It ends in 2014 — not showing the temperature spike in 2015-16, which considerably closed the gap.
(3) It ignores the more accurate surface temperature measurements. For example, compare the size of the adjustments made new versions of the satellite data vs. surface data. The former are much larger than the former.
(4) Models cannot predict short-term temperature variations. Valid comparisons require longer time horizons.
(5) There is a large literature on this. I suggest you look at it. Articles by two advocates of Cato Institute are not a reliable source to understand the consensus of climate scientists.
Edge – I see that you are convinced. Both sunspot decline and ocean cycle decline are pointing down for temperature but water vapor is rising much faster than it should based on temperature alone and water vapor increase means pointing up. Conclusion, too close to call (or bet on) for me and besides I doubt I will last 10 more years. My projection (shown in Fig 15) depends on what the sun does. You can compare actuals as they develop.
FM – I have not seen anything more recent. Spencer’s earlier work shows the comparatively wide scatter in GCM runs. http://www.drroyspencer.com/2013/06/still-epic-fail-73-climate-models-vs-measurements-running-5-year-means
Yes the super El Nino shows as the 2015-16 spike. I have been plotting the monthly reports and the trend has been down since Feb, 2016 (but with an uptick last month). I see no reason to change the projection in Fig 15 or the assertion that ‘climate sensitivity’ to CO2 is not significantly different from zero.
I use HadCRUT4 for comparison with my calculations. The GCM runs were calculations not measurements. Everybody is trying to determine average global temperature and it’s the changes with time that matter and should be OK providing the method used to determine them does not change. Agencies changing earlier data is problematic.
I agree re short term runs. My analysis uses data 1895-2015. IMO measurements prior to 1895 were not sufficiently reliable world wide.
The Consensus has come up with a lot of misleading stuff. I discuss some of their mistakes here: http://consensusmistakes.blogspot.com
CO2 20 yr level trend-
FM – “cannot be predicted”.
Edge – Higher (and accelerating)
GAT 10 yr trend –
FM – “climate models cannot yet make reliable predictions for five to ten years horizons”
Dan – “Too close to call”
Edge – Higher
My very rough “model” makes predictions. The atmosphere contributes about 33 deg C to the GAT. CO2 contribution is in the neighborhood of 10% of that. C02 concentration increases fast and steadily, due to human activity. It raises GAT, given all other variables equal. All other variables (sun, volcanoes, EN, etc.) are not equal, but they will not lower the temperature enough (some add to it temporarily). They are not as strong individually and are not synchronized.
I suggest you read the IPCC section about modeling. You confuse “projections” with “predictions”. Predictions are made on the basis of scenarios, assumed future conditions (e.g., emissions, volcanic activity, etc). The RCPs in IPCC’s AR5 describe paths to create four scenarios — assumptions about technology, population, GDP, etc. Those scenarios are run through models to create forecasts of future temperatures. Since we cannot reliably predict future global conditions, we can only guess at which scenario will prove most accurate — so we get a wide range of lines on the graph of time vs future temp.
“My very rough “model” makes predictions. ”
Anyone, even children, can make predictions. Reliable predictions of shorter-term climate — under 10 years — are beyond the state of the art. If you can do so, I suggest publishing. Perhaps there’s a Nobel Prize in your future.
Thank you for your contribution. To help you concentrate on your great work, your future comments are moderated. Anything citing real sources will be posted. Claims about your science expertise will not.
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No methane monster? What about the 7000 new methane bubbles reported in Russia just a few days ago?
Do you have surveys of Russian methane bubbles from the 16thC, before the Little Ice Age cooling? The world has been warming for two centuries (starting long before substantial effects from antropogenic CO2). Of course there are effects. But the 19th C (aka “pre-industrial) was not the unchanged and unchanging Eden before the industrial fall.
Rather than panic at the latest sensational news (Earth-ending dooms reported daily!), I suggest you watch the reports of the IPCC and the major climate agencies. There are a host of scientists watching methane levels. When there are reliable conclusions, they’ll tell us.
About the latest panic attack — from Russia. This is how “telephone” is played by children.
(1) TASS reports about something on March 14: “Ученые обнаружили около 7 тыс. подземных газовых пузырей в ЯНАО“.
(2) The “Siberian Times” website runs a story on March 20 about the TASS story: “7,000 underground gas bubbles poised to ‘explode’ in Arctic“. Do you know anything about them? I doubt it. Their “About” page says nothing, giving just an address and telephone number.
(3) Western media pick it up, rebroadcasting it with addition of comments by western scientists who have just read the 3rd hand story. Note that the WaPo doesn’t cite the TASS story, just the 3rd hand Siberian Times story (perhaps budget cuts prevented hiring a translator): “Russian scientists find 7,000 Siberian hills possibly filled with explosive gas.” Excerpt:
So you can panic, if it makes you happy. I’ll wait for useful information from the major science agencies.
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