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Bad Climate Outcomes — Atmospheric Warming to Ramp up as PDO Swings Strongly Positive?

Last year, quietly and without much fanfare from the mainstream press, the Pacific Ocean underwent a powerful shift. A shift from a state in which cooler surface waters absorbed atmospheric heat, to a phase in which surface water warming caused ocean heat to be transferred to the world’s already warming airs.

The shift was heralded by a powerful oceanic Kelvin Wave. One that brought warm water up from the depths and spread them across the Pacific Ocean surface. Ever since that time, warm Kelvin Waves have continued to refresh this surface water heat pool.

monster-el-nino

(Major Kelvin Wave that heralded a switch to strongly positive PDO values for the Pacific. Image source: NOAA/ESRL)

And so the Pacific Ocean surface warming continued throughout 2014.

By December, Pacific Decadal Oscillation (PDO) values, a measure directly tied to this warming, hit a new all-time record level of +2.51. That’s the highest and hottest PDO value since record-keeping began in 1900. One that only backed off slightly into January at +2.45 in the preliminary measure.

It’s a major swing in Pacific Ocean surface temperatures to a phase where more heat is dumped into the atmosphere. One that is causing some scientists to warn that a new period of rapid atmospheric warming may just be getting started.

image

(Sea surface temperature anomaly map shows very warm surface waters dominate much of the equatorial, eastern and northern Pacific in a signature that is strongly characteristic of a powerfully positive PDO on Thursday, February 26 2015. Image source: Earth Nullschool. Data Source: Global Forecast Systems Model.)

PDO and The Multi-Decadal Heat Pump

Pacific Decadal Oscillation (PDO) is a periodic change in sea surface temperature states in the Pacific. One that is thought by many oceanic and atmospheric researchers to have a strong influence on global weather and temperature variability.

In the negative state, PDO tends to encourage La Nina events which also coincide with a downswing in global temperatures as the vast Pacific waters take in more heat. In the positive state, PDO tends to encourage El Nino events which result in the great ocean belching heat into the air on a grand scale — pushing atmospheric temperatures higher.

All things being equal, this natural variability would pan out — marking upswings and downswings in a global average. However, human fossil fuel burning and related greenhouse gas emissions have bent this curve upward by trapping more and more heat in the lower atmosphere. So the case is now that during positive PDO phases, in which more El Ninos occur, atmospheric warming has tended to ramp drastically higher. And, consequently, during negative PDO phases, atmospheric warming has tended to merely slow down even as oceanic warming sped up.

You can see this speeding up and slowing down in the below graphic provided  by Weather Underground:

PDO vs global temperature change Weather Underground

(Global temperature change since 1900 vs phases of positive PDO [1925 to 1945 and 1975 to 1998] and negative PDO [1945 to 1975 and 1998 to 2014]. Image source: Weather Underground. Data Source: NOAA.)

In the era during which global temperatures have been increasingly driven by human greenhouse gas emissions, four phases of PDO have been recorded. Two were positive, two were negative.

In the first positive PDO phase during 1925 through 1945, global average temperatures jumped upward by about 0.5 degrees F (+0.25 F per decade). This initial surge in atmospheric warming abated as global temperatures remained roughly steady during the negative PDO period of 1945 to 1975 (+/- 0 F per decade). But by 1975, PDO values were positive again and the period through 1998 showed a rapid warming of about 0.8 F over 23 years (+0.4 F per decade). After the super El Nino of 1998, PDO values again trended negative as atmospheric warming continued at a somewhat slower pace of about +0.15 F per decade.

Global Warming and Related Ills to Ramp Up?

This underlying trend should be cause for serious concern.

The first issue is that we see warming now during negative PDO decades where we only saw cooling or zero warming before. Given the present rate of warming in the range of +0.15 F per decade during periods in which the Pacific Ocean is taking on atmospheric heat, one could expect the next positive PDO phase to see decadal warming in the range of +0.55 F or higher (or by about 1 C in 20-30 years).

Such a rapid pace of warming could challenge the fabled 2 C ‘point of no return’ before 2050 (for reference, we are at about +0.85 C above 1880s values now). And it is for this reason that some scientists are now starting to sound alarm bells.

In the recent Weather Underground commentary penned by Jeff Masters, Kevin Trenberth, an NCAR scientist and one of the world’s foremost experts on ocean temperature dynamics, noted:

“I am inclined to think the hiatus [in global temperature increases] is over, mainly based on the PDO index change. If one takes the global mean temperature from 1970 on, everything fits a linear trend quite well except 1998.”

NOAA global surface temperature anomalies

(Global surface temperature anomalies. Image source: NOAA.)

Though Trenberth does not explicitly spell out the potential for an overall warming acceleration, he does point toward a return to the +0.29 F per decade trend line seen since 1970. Meanwhile, Matthew England of the University of South Wales warned in the same Weather Underground commentary that any post ‘hiatus’ warming would be likely to be very rapid.

Dr. Michael Mann, a climate scientist of considerable fame both due to his Hockey Stick tree ring study and due to his ongoing success fighting off smear campaigns launched by climate change deniers, recently put together climate model assessments that showed world temperatures exceeding the 2 C threshold by 2036 under business as usual greenhouse gas emissions. To reach such a high reading so soon would require in excess of 1 degree Fahrenheit warming over each of the next two decades. And such a rate of warming would be very rapid indeed, unprecedentedly rapid and well outside the linear trend line from 1970.

Michael Mann today made related comments at Realclimate on the more recent oscillations in Pacific Ocean sea surface temperature:

There is the possibility that internal, natural oscillations in temperature may have masked some surface warming in recent decades, much as an outbreak of Arctic air can mask the seasonal warming of spring during a late season cold snap. One could call it a global warming “speed bump”. In fact, I have… Given the pattern of past historical variation, this trend will likely reverse with internal variability, instead adding to anthropogenic warming in the coming decades. That is perhaps the most worrying implication of our study, for it implies that the “false pause” may simply have been a cause for false complacency, when it comes to averting dangerous climate change.

To these points, it is worth noting that any rate of warming above 0.3 F (0.2 C) per decade is extraordinary and terrifying. Such a rate is enough to achieve post ice age warming of 4 C in merely 2 centuries where it took 10,000 years to achieve such warming before. Warming at 0.4, 0.6 or 1 F per decade would be both drastic and devastating to current climates, geophysical stability, weather stability, glacial stability, water security, food security, and ocean health. In the current world, already warmed by about 0.85 C above 1880s levels any acceleration to current warming is a rather bad outcome on top of an already dangerous situation.

Links:

Are We Entering a New Period of Rapid Global Warming?

Climate Oscillations and the Global Warming Faux Pause

NOAA’s National Climate Data Center

NOAA’s Earth Systems Research Lab

Monster El Nino Emerging From the Depths?

Far Worse Than Being Beaten With a Hockey Stick: Michael Mann Climate Model Shows 2 C Warming by 2036

Global Warming Speed Bump? The Answer May be Blowing in the Wind.

Earth Nullschool

Global Forecast Systems Model

Hat Tip to Colorado Bob

Hat Tip to Bassman

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Deep Ocean Warming is Coming Back to Haunt Us: Record Warmth for 2014 Likely As Equatorial Heat Rises

As prominent ocean researcher and climate scientist Dr. Kevin Trenberth presciently noted during recent years — an observed spike in ocean heat content over the past decade may well be coming back to haunt us.

Earlier this year the most intense sub-sea Kelvin Wave on record raged across the Pacific Ocean. Driven eastward by a series of strong westerly wind bursts, it traveled just below the surface, running out to collide with South America. By April, it had arrived in the traditional El Nino spawning grounds of the Eastern Equatorial Pacific where it retained an extreme intensity. There it sprawled, snuffing off the cold deep water upwelling that over the past few years has kept surface water temperatures in this critical region slightly cooler than average.

And so, from late March through mid-May, the Eastern Pacific warmed.

A surface warm pool sprang off the back of this beast, growing even as it continued to gather heat, radiating it back into the atmosphere. By yesterday, temperature anomaly values over this growing region had increased to between 1 and 3 C above average with local spikes up to +3.9 C — a far above normal temperature departure for ocean surface waters, especially near the stable equator. But if trends hold, this is just the beginning. An early start to what could be a record-setting event.

Today's GFS Model Summary of Sea Surface Temp Anomalies

(Today’s GFS model summary of global sea surface temperature anomalies. See the mottled red just off South America? That’s the head of an extraordinarily strong and massive Kelvin Wave breaking the surface. Image source: University of Maine.)

Today’s GFS global ocean temperature anomaly map shows the entire Equatorial Pacific well in the El Nino range at +0.60 C. The strong +1 to +3 C or greater hot zone, shown in orange to deep-red, stretches from about 140 West to 80 West Latitude along the equator and shows continued slow intensification.

Note that global sea surface temperatures for today are at an extraordinary +1.12 C above already warm 1979 to 2000 values. This marks more than a week of 1 C or greater positive ocean surface temperature anomalies. The very definition of Trenberth’s ocean heat content coming back to haunt us.

The El Nino Clock Begins

Meanwhile, NOAA weekly anomaly readings also show continued progression toward surface warming. Overall, the Nino zone 4 in the Central Pacific was at +0.8 C, the Nino 3.4 zone in the East- Central Pacific +0.5 C, the Nino 3 zone in the Eastern Pacific +0.6 C, and the Nino 1+2 zone just off the coast of Equatorial South America a very high +1.2 C. Overall, this shows strong warming over the broad Nino sector with the key Nino 3.4 zone flipping into low El Nino levels this week.

The emergence of Nino 3.4 into +0.5 C or greater territory marks the start point for the NOAA El Nino clock. For NOAA to declare El Nino, the Nino 3.4 zone must remain at +0.5 C or above for multiple months running. And forecast models, at this time, show nearly an 80% likelihood of just such an event for 2014.

So this week’s readings represent the crossing of a new threshold toward El Nino and certainly warrant further tracking.

Monster Kelvin Wave in Not-so-Cool Phase

The extreme Kelvin wave that raged across the Pacific from February through April still appears monstrous even though it has now entered its supposedly cool, upwelling phase. Pressed against the coast of South America, the heat has deflected both upward and downward through the water column. The result is both a continued heating at the surface and a downward thrust of 1-2 C above average water temperatures into the 400 meter below surface zone. And so here we have a continued down-thrust of the 20 C isotherm, priming the Pacific for another west-to east rush of deep ocean heat later this year.

Monster Kelvin Wave May 8

(This is supposed to be the Kelvin Wave’s cool phase. It’s not looking very cool. Image source: NOAA.)

Overall, the still amazingly hot Kelvin Wave is upwelling. So it should also be cooling. And it has. A little. But what is extraordinary is the amount of heat it has retained even as it rises. Here we see an enormous slug of 5-6 + C above average water rising as high as 40 meters beneath the surface. Maintenance of this high heat content even while upwelling is an insane feat of heat propagation. Should these readings hit the surface, we really will be witnessing a monster event.

Already, the warming Eastern Pacific appears to be having a broader atmospheric affect. According to NASA, global surface temperatures spiked to their second highest level on record in April. Meanwhile, GFS model analysis shows May daily surface temperature values in the range of +0.7 to +1.0 C or higher above the 1950 to 1981 average globally. A continuation of these high temperatures would be enough to put May at first or second hottest on record and set a trend for 2014 to break global high temperature records last seen in 2010. So the early and not yet fully developed ocean surface heating we are seeing from our developing El Nino appears to have already come back to haunt us. But what we see now is minor compared to what could emerge.

With the sub-surface waters remaining so extraordinarily warm even through the upwelling/cool phase of the current Kelvin Wave, the Pacific is now primed for a second hot pulse to feed the monster now rising off South America. The new, reinforcing heat pulse will require another series of west wind back bursts at the surface between 160 East and 170 West Longitude to drive it. And atmospheric conditioning for the development of these winds appears well in play. Should it happen, we are likely to get a taste of what Dr. Trenberth really meant.

Dr. Trenberth Hints at PDO Flip

Along with these sobering thoughts, I leave you an excellent related interview Peter Sinclair conducted with Dr. Kevin Trenberth. In the interview, Trenberth predicts a + 0.2 to 0.3 C rise in global average temperatures due to Pacific Ocean surface heating and hints that a flip in the Pacific Decadal Oscillation (PDO) from its current cool (negative) phase to a new warm (positive phase) may well be underway. Such a flip would indeed mean that a rapid spike in global surface temperatures is in the offing:

Links:

University of Maine

Monster El Nino Rising From the Depths

NASA: April 2014 was Second Hottest on Record

Ocean Heat Anomaly Spikes to New Extreme High of +1.16 C Above Average on May 10, 2014

Forecast Models Show Nearly 80% Chance of El Nino in 2014

Kevin Trenberth on El Nino

NOAA’s Climate Prediction Center

Pacific Decadal Oscillation (PDO)

 

 

 

The Economist Continues its Wallow Through Climate Sensitivity Denial

Good News...

Delaying action on climate change is suicidal. Yet the Economist wants you to believe it’s not such a big deal.

(Image source: League of Conservation Voters)

In desperately scanning through the IPCC’s preliminary 4th assessment report for any shred of good news, perhaps in hopes of delaying a transition away from fossil fuels that needs to begin now and complete by 2030-40 if we’re to have much hope of ensuring a climate in which human civilization won’t face catastrophe, The Economist found a bright little cherry. It reproduced a preliminary graph from a non-physical sciences group showing lower than scientific consensus estimates for temperature increase through 2100 and conflated it with an entirely Economist-manufactured news item erroneously stating scientists are finding climate sensitivity is lower than previously expected (Hint: it’s not).

I’m not going to re-publish the graph, as it’s entirely misleading, but I will re-publish what The Economist says about it:

Still, over the past year, several other papers have suggested that views on climate sensitivity are changing. Both the 2007 IPCC report and a previous draft of the new assessment reflected earlier views on the matter by saying that the standard measure of climate sensitivity (the likely rise in equilibrium temperature in response to a doubling of CO2 concentration) was between 2°C and 4.5°C, with 3°C the most probable figure. In the new draft, the lower end of the range has been reduced to 1.5°C and the “most likely” figure has been scrapped. That seems to reflect a growing sense that climate sensitivity may have been overestimated in the past and that the science is too uncertain to justify a single estimate of future rises.

Note the Economist’s highly speculative use of the words ‘suggest’ and ‘seemed.’ And ‘scientists,’ in this case, apparently include only those on the low end of climate sensitivity estimates, rather than the more likely to be accurate consensus range. Research on the middle or high end, likewise, is completely ignored.

Quibbling Over Equilibrium Sensitivity

The Equilibrium Climate Sensitivity (ECS) The Economist refers to is how much Earth temperatures are expected to rise when one includes fast feedbacks such as atmospheric water vapor increase and the initial greenhouse gas forcing provided by CO2. Consensus science, despite The Economist misinforming us to the contrary, finds Equilibrium Climate Sensitivity to be about 3 degrees Celsius for each doubling of CO2. So we get around 3 degrees Celsius of rapid warming at 550 parts per million, according to mainstream science. The Economist’s misleading quibble is trying to suggest that this level is closer to 2 degrees Celsius or the ludicrously unsupportable 1.5 degrees Celsius. Measures that, even if it were true (it’s not), would buy us, at most, another decade or two of business as usual emissions.

As unfortunate as the Economist’s cherry picking has become, it doesn’t even melt the tip of the iceberg or permafrost, for that matter. Because if you include the ‘slow feedbacks’ that ECS leaves out you end up with double the amount of warming long-term. So 550 parts per million gets us to a scorching 6 degrees Celsius Earth Systems Sensitivity (ESS) once melting ice sheets, methane release, and permafrost thaw are included (consensus estimates, not what The Economist cherry picked). The Economist also seems to ignore the blatant fact that such feedbacks are emerging now. Amplifying methane release in the Arctic has been visible since the mid 2000s and Greenland and West Antarctic melt rates have been increasing at an exponential rate since about 1995.

Confirming these observations is a new paper showing Greenland ice sheet response is happening faster than scientists expected. With the Greenland ice sheet melting like butter now and not 100 years from now as IPCC originally expected, the Equilibrium Climate Sensitivity measure and its inherent assumption that ice sheet and tundra response will be slow, seems to be shaping up as too conservative. Yet, The Economist remains enchanted with the notion of warping these already conservative estimates to pad its own, more comfortable, view of reality.

How’s the sand you’ve got your head buried in, Economist? Soft and white? Watch out, heads buried in the sand tend to bake these days.

What should be the news all responsible mags are reporting is that the ‘slow feedbacks’ aren’t really so slow after all. Under the very rapid pace of human forcing of at least 10 times anything we can find in the geological record Greenland melt, Antarctic melt, tundra melt and methane release are coming into play now. All taken together, they will more than double the human forcing. Terrifying news that should have all responsible persons and governments pushing for a rapid response, not grasping for the lowest hanging cherries in the science reports.

So the real measure we should be concerned about now is the one that includes all or most of the feedbacks — the Earth Systems Sensitivity (ESS) we noted above. The real total estimate of warming that is at least twice the academic ECS estimate The Economist so desperately tried to water down.

Yet the magazine behaves well contrary to prudent logic as it merrily runs with its false claim that climate scientists are saying ‘we’re sorry we scared you, climate sensitivity is less than we previously expected.’ Sad to say, The Economist is entirely involved in the now too common journalistic sin of climate science misinformation via massaged data.

Joe Romm notes:

The good news is that The Economist article might be less dreadful than it could have been. For instance, I didn’t find any typos…

The Economist seems blissfully unaware that while the Thawing Permafrost Could Cause 2.5 Times the Warming of Deforestation (!) and add up to 1.5°F to warming in 2100 by itself, “Participating modeling teams have completed their climate projections in support of the [IPCC’s] Fifth Assessment Report, but these projections do not include the permafrost carbon feedback.

The Economist also seems blissfully unaware of the fact that we are currently close to the 1000 ppm emissions pathway. And The Economist also seems blissfully unaware that stabilizing anywhere near 450 ppm atmospheric concentration of CO2 would require immediate and sustained action to replace the world’s fossil fuel system with one based on carbon-free energy — precisely the kind of aggressive action this piece seems designed to undercut.

For my part, I’d prefer more typos and less misleading information on the science.

Perhaps The Economist should take a look at the best of the best among climate scientists — notably James Hansen who warns that Equilibrium Climate Sensitivity is at least 3 degrees Celsius and that this estimate is probably conservative. Hansen finds that under business as usual greenhouse gas emissions we reach a scorching 7 degrees Celsius warming and very catastrophic 1,000 parts per million CO2 by the end of this century (if we somehow manage to hold industrial civilization together after we blow through 2, 4 and 6 degrees Celsius worth of warming, which is highly unlikely). The final warming in such a case, Hansen shows, would be between 10 and 14 degrees Celsius — enough to trap the climate in a PETM-type warming in less than one century, and blast humans with large areas of lethal 35 degree Celsius or greater wet bulb temperatures. A mass extinction event for us humans and all other life too.

Michael Mann, another top climate scientist The Economist ignores by sticking its fingers in its ears and chanting ‘nanananana’ notes:

Among other things, the author [of the Economist’s report] hopelessly confuses transient warming (the warming observed at any particularly time) with committed warming (the total warming that you’ve committed to, which includes warming in the pipeline due to historical carbon emissions). even in the best case scenario, business as usual fossil fuel burning will almost certainly commit us to more than 2C (3.6 F) warming, an amount of warming that scientists who study climate change impacts tell us will lead to truly dangerous and potentially irreversible climate change. the article does a disservice to Economist readers by obscuring this critical fact. Sadly, it is hardly the first time in recent history that the Economist has published flawed and misleading stories about climate change.

Mann shows that The Economist clearly misses some very basic principles of climate science by confusing projected warming at a particular point in time with final warming. And that’s a big problem. Because temperatures will continue to move higher for decades, even if we were to halt emissions immediately, which is clearly not in the Economist’s plans. The Economist’s plans, instead, seem to include locking in more dangerous exploitation of fossil fuels.

Since the Economist clearly can’t handle ECS, it should stick with Paleoclimate, which is much less murky. And by looking back into Earth’s geological history we find temperature increases at these ranges for these levels of carbon dioxide:

350-400 parts per million: 3 degrees (C) worth of temperature increase long-term (Greenland and West Antarctica melt).

400-450 parts per million: 4 degrees (C) worth of temperature increase long-term.

450-500 parts per million: 5 degrees (C) worth of temperature increase long-term.

500-600 parts per million: 6 degrees (C) worth of temperature increase long-term (No major glacial ice left).

600-700 parts per million: 7 degrees (C)…

700-800 parts per million: 8 degrees (C)…

800-1200 parts per million: 9-12 degrees (C)…

Add to these observed past warming levels the fact that the rate of forcing was much slower than the human rate of forcing. So if more forcing means more feedback, even the harsh Paleoclimate evidence is too conservative a measure. Hansen and others warn of ‘unexpected consequences’ from the rapid pace of human forcing. And it would ‘seem’ that one of these nasty surprises is an already observed faster than usual rate of ice sheet and methane response.

Climatologist Kevin Trenberth is another scientist The Economist seems to be happy to ignore. But, perhaps, they should listen and learn something. In a letter to Joe Romm, Kevin stated:

The Working Group III IPCC report [on mitigation which the Economist used in its most recent attempt to misinform on climate sensitivity] is no where near final, the final draft has not even been produced yet. Moreover WG III is not responsible for making any statements about climate sensitivity and have no business doing so. The IPCC parallel process hinders exchanges among WGs and the WG I results [on the physical science basis]may not be available to WG III, but will be in due course as there is some staggering of the reports. In the meantime, the Economist report is irresponsible.

So The Economist is, in essence, bending over backwards to manufacture its own data. And after past media mistreatment of the last IPCC report, should we be surprised?

To this point, I would add that the responsible action would be to err on the side of caution, not on the side of laissez faire. In markets, laissez faire often leads to monetary collapses the consequences of which are often recessions. In the case of climate change, laissez faire leads to your civilization, species and large swaths of the natural world in complete wreckage.

We know what the long-term consequences of a certain level of CO2 are. And we know that slow feedbacks might not be so slow under the fast forcing regime we’ve subjected the Earth’s climate to. We also know that we have very little wiggle room for human comfort and prospertity — at best 2 degrees Celsius of warming. So why would we want to, as The Economist does, downplay the problem and risk a dangerous delay of action?

With dangerous and difficult consequences emerging now, we would be insane to follow The Economist’s implicit and falsely comforting advice. Trenberth is right. The report is dreadfully irresponsible as it weakens the case for a necessary and urgently needed response to the harm that is surely coming.

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