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Polar Amplification, El Nino or Both? NASA Shows October of 2015 Was Hotter Than All of the Previous 1617 Months

If it seems we are doing a never-ending marathon of hottest posts, it’s simply because the world right now is ridiculously hot. Hotter than at any time ever seen before and being driven inexorably hotter by a combination of human greenhouse gas emissions and what appears to be a global warming weirdified El Nino that doesn’t look anything like a normal El Nino, but instead shows up as an intense blob of extreme heat sitting in a massive hot blob that makes up pretty much all of the Pacific Ocean from the Equator on north.

Busting the Top of the Global Temperature Graph

It’s in this rather crazy weather context that we find, according to NASA, October of 2015 set the bar for new hottest month in the global climate record for all of the past 135 years. That’s right, out of 1618 months in NASA’s global climate record, when comparing current readings to rolling baseline temperature averages, October of 2015 was the hottest one ever seen. A confirmation of the Japan Meteorological Agency’s findings from earlier this week. But one that, in true NASA fashion, also provides a boatload of additional data worth peeping at.

NASA global temperature graph

(With one month remaining in the December-through-November climate year, global temperature averages for the first 11 months of 2015 are now +0.819 C above the 1950-1981 NASA baseline. With November also likely to come in between +0.90 and +1.1 C hotter than normal, the 2015 yearly average is likely to come in well above the top of the chart. Image source: NASA GISS.)

Taking a glimpse at NASA’s Land-Ocean Temperature Index (LOTI), we find that October of 2015 came in at an extraordinary +1.04 C hotter than the 1950 to 1981 average or about 1.26 C hotter than 1880s averages. That’s an extreme temperature departure hitting within 0.74 C of the so-called safe limit of 2 C warming set by the UN. To put into perspective how weird and scary it is to hit such a high temperature departure, the last time temperatures were so high globally for any period of note, sea levels were between 10 and 30 feet higher than they are today. It’s another unfortunate passing of another bad climate marker on the way toward worse and worse to come if we can’t manage to stop emitting so much carbon into the atmosphere.

Overall, October of 2015 beat out the previous record hot month of January of 2007 (0.97 C above the NASA baseline) by 0.07 C. It is also the first month in the NASA monitor to exceed 1 C above the mid-to-late 20th Century range. In total, all of the top five hottest months in the global climate record have now occurred since 2007 with October 2015 (+1.04 C) coming in as hottest, January of 2007 (+0.97 C) coming in as second hottest, March of 2010 (+0.93 C) third hottest, March of 2015 (+0.90 C) fourth hottest, and September of 2014 (+0.89 C) as fifth hottest. But with the monster El Niño blowing up in the Pacific and with atmospheric greenhouse gasses pushing above 400 ppm CO2, it’s likely that many of these top five months could be replaced by new records into early next year. Moreover, the three month period of September, October, and November of 2015 now looks like it will be the first quarter year to exceed +0.9 C above the 1950-1981 baseline in the NASA record.

Warm Equator, Heating Poles

Moving on to NASA’s geospatial temperature anomalies map for the month of October, we see that much of the abnormal heat remains centered at the Poles. This despite a Godzilla El Nino belching hot air into the Equatorial region and pushing a strongly positive Arctic Oscillation. High polar temperature anomalies are an odd result during powerful El Nino periods due to the fact that warming at the Equator tends to strengthen the Polar wind field, locking cold into the upper and lower Latitudes. But over the past two months, Polar temperatures have remained extremely high despite what looks like the most powerful El Nino ever recorded tearing its way through the Pacific.

Global temperature anomalies map October of 2015

(This is what a record hot world looks like in NASA’s global temperature anomalies map. Note both the heat at the Poles and Equator along with the melt and ocean heat uptake related cool pools in the North Atlantic and Southern Ocean. Image source: NASA GISS.)

With such high polar temperatures giving what amounts to an atmospheric back-hand to the strongest El Nino on record, it’s a sign that a raging greenhouse gas driven polar amplification is becoming ever more heavily entrenched. The poles, in short, are more sensitive to global temperature swings and tend to amplify any overall warming or cooling trend. Such an additional sensitivity is due to a number of unique feedbacks that come into play in the upper Latitudes as greenhouse gas levels and global temperatures rise or fall. A circumstance that was predicted in even the earliest global climate model runs forecasting the impacts of a human forced heating of the Earth System. And it appears that this feedback-generated added warming is starting to take hold with a vengeance.

Overall, we find the highest temperature deltas in the Arctic Ocean just north of the Kara Sea, over various regions of the far South Antarctic, and over Central and Western Australia. These regions ranged into an extreme +4 to +5.1 C positive anomaly for the month. Broader warm regions featuring +2 to +4 C above average temperatures surrounded these hot zones. Strong warm temperature departures in this range also held sway over the Eastern Equatorial Pacific El Nino hot spot, over a band from North Africa through the Middle East, over the Lake Baikal region of Russia, and over South Africa.

Equator-to-Pole heat transport — another feature we really don’t like seeing — also remained plainly visible in the October NASA anomalies graphic. Two slots of warm air transport into the northern polar zone show up clear as day in the above graphic — one maintaining over Western North America and another holding sway over Northeastern Asia.

Somewhat cool regions include the heat sink zone in the Southern Ocean, the tip of South America, Eastern Europe, and the ominous Greenland melt related cool pool in the North Atlantic (something we also really don’t want to see). Overall, most of the world showed above average readings with cooler regions increasingly isolated on the NASA map.

zonal anomalies NASA

(Zonal anomalies map shows a strong polar amplification despite El Nino. Image source: NASA GISS)

At last coming to the zonal anomalies graphic, we again observe a very strong polar amplification for the month of October. Here we note that the highest global temperature anomalies occur at both the South and North Poles. These extreme temperature spikes in the range of +3.3 to +3.5 C above average for the month are plainly visible in the upward tilting ‘devils horns’ (another unfortunate climate change indicator) at both the left and right border of the graph. As we move toward lower Latitudes, temperature departures rapidly fall off into the global cool and stormy zones between 50 and 60 North and South Latitudes. Anomalies then steadily climb to an El Nino-warmed Equatorial region (+1.2 to +1.4 C).

November of 2015 Also Likely to Test New Records

Looking toward November, early indications are that both the record or near-record global surface temperatures and the tendency for polar amplification continue. Land and ocean temperatures appear to have extended their October jump into new record ranges. El Nino, which under the regime of human-forced warming has often nudged global temperatures toward ever-hotter extremes, likely pushed sea surface temperatures to new all-time highs in the Equatorial Pacific for the month. Such a huge amount of heat bleeding off this broad ocean zone will likely to continue to spike global surface temperatures. Given such a context, it appears that we’ll be under the gun for new global surface temperature records for a period of at least the next 4 months. So what we saw during October was almost certainly just the start of the current global temperature spike.

Links:

NASA GISS Surface Temperature Analysis

NASA GISS

NASA Land Ocean Temperature Index

Polar Amplification

October of 2015 Shaping up to be Hottest Month Ever Recorded

 

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NASA: October 2014 Tied For Hottest on Record

October 2014 Hottest on Record

(October was again a global temperature record setter. Image source: NASA.)

NASA’s monthly global temperature analysis is in and the results are once again record-making. For according to NASA’s global monitor, world temperatures were 0.76 degrees Celsius above the Earth average for the mid 20th Century.

This high temperature departure ties 2005 for hottest in NASA’s 136 year record. A temperature level that global ice core data points toward being hotter than at any time in the past 130,000 years. A record hot month in a string of record hot months for 2014. A resurgence to record high marks amidst an unprecedented spate of rising temperatures that has lasted now for more than a century running.

Global land ocean temperature index

(Global temperatures have risen by more than 1 degree C above their low mark at the start of the 20th Century. It is a human-driven pace of warming 15-20 times faster than at the end of the last ice age. Image source: NASA)

Polar Amplification Again Prominent

As in recent months, hottest temperatures were again focused near the poles. The northern polar region in particular observed much hotter than normal readings with a very large zone experiencing +2 to +5.5 degrees C above average temperatures for the entire month. East Antarctica also saw much warmer than normal temperatures with monthly averages spiking from +2 C to more than 4 C above the 20th Century average.

Overall, much of the world showed hotter than normal temperatures with cooler than normal readings confined to sections of the Southern Ocean and Eastern Europe. Small and isolated pockets of cooler than normal readings were found in diminutive oceanic zones. Meanwhile, the rest of the world experienced warmer than normal to much warmer than normal readings.

zonal readings October

(Zonal temperature departures by latitude. Image source: NASA)

Zonal readings also showed very strong polar amplification in the Northern Hemisphere with surface temperatures averaging at 2.6 degrees Celsius above normal in the region above 75 degrees North Latitude. A spike in temperature to +1.3 C above average was also observed in the region of 80 degrees South Latitude.

The Southern Ocean again appears to be the primary zonal heat sink as the only region showing below average temperatures in the range of -0.38 C below average. As we have seen in previous analysis, this region is currently the principle atmosphere-to-ocean heat transfer band. Ocean heat uptake in this region has been shown through recent studies to have resulted in very rapid warming of the top 700 meters of Southern Hemisphere ocean waters. It has also played a role in the more rapid glacial destabilization observed among Antarctica’s increasingly fragile ice sheets and ice shelves.

Polar Amplification Sees Late Fall Vortex Disruption, Severe Dipole Anomalies

Northern Hemisphere polar amplification is a primary contributor to the polar vortex disruptions and extreme Jet Stream distension we’ve seen since about 2005. Current conditions also indicate an extraordinary dipole again developing with heat pooling in the Arctic near Alaska and in the maritime zone between the Kara Sea and Greenland. Already in November, this has caused an extreme meridonal avection of polar cold air over the continents even as warm air drives north toward the pole over Atlantic and Pacific Ocean regions.

Arctic Anomaly Map

(Warm air invasion of the Arctic forcing temperatures to 1.9 C above average drives polar air over Central Asia and Eastern North America on November 19 of 2014. Such displacements of cold air during Northern Hemisphere winter are directly tied to global-warming related polar amplification. Image source: GFS/University of Maine)

2014 Close to Hottest On Record

Currently, NASA’s global temperature average for the first ten months of 2014 puts the year at 0.664 C above the global average. 2010, the previous hottest year on record, stood between 0.66 and 0.67 degrees hotter than the 20th Century average. So we are now in record-making territory for 2014. Any further months with average temperatures above 0.67 C would continue to cement 2014 as a new record holder.

In any case, the excessive heat for 2014 is at least likely to place it among the top 1-4 hottest years even if November and December show less extreme warm temperature departures. An extraordinary degree of warmth for a year in which official El Nino status has yet to be declared.

With global political leaders retaining an overall laissez faire attitude to positive action on climate change and with powerful fossil fuel interests gaining power in the US Congress (Republicans), it is unfortunately very likely that ongoing massive greenhouse gas emissions in the range of 50 billion tons of CO2 equivalent each year will continue to add more heat to the world’s oceans, atmosphere, and glaciers. As time moves forward, this will vastly increase the risk of catastrophic weather and geophysical change events. We see such events now in Brazil, California and across an expanding range of regions. But these early outliers are mild compared to the potential extremity of events as time moves forward and catastrophic emission rates increase.

As with other brands of risk, including financial risk, the world’s current economic and political leaders have shown a terrible ineptitude in working to prevent catastrophic and destabilizing loss. One hopes that political and economic leaders will wise up. But, currently, there is very little to indicate that urgently needed changes will be forthcoming.

Links:

NASA GISS

GFS/University of Maine

IPCC 2014: Adaptation and Vulnerability

(Note edited to include the Eemian, which is probably still hotter than this monthly average by about 0.8 to 0.9 C at peak warming)

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