Andrew Freeman is right. It’s been a cruel, cruel summer. Hothouse mass casualty events, spurred by a ridiculous accumulation of heat trapping gasses in the Earth atmosphere, have spanned the Northern Hemisphere. The result has been thousands of lives lost and the hospitalization of tens of thousands more as global temperatures rocketed to levels not seen in probably 100,000 years (related — Hothouse Mass Casualties Strike Egypt).
July of 2015 Hottest on Record
Now, in a record-shattering hot year featuring extreme weather weirdness and an emerging monster El Nino, yet one more record has fallen. For according to both NASA and Japan’s Meteorological Agency (JMA), July of 2015 squashed and smashed previous record hot Julys 2011 (NASA) and 1998 (JMA) to take the title as hottest July yet.
(Japan’s Meteorological Agency shows July of 2015 was the hottest on record by a wide margin.)
In the JMA graph, beginning in 1890, you can plainly see the new July record is well above the +0.67 C per Century warming trend line of the last 125 years. A new high that leaves the 1998 super El Nino year in the dust.
For JMA, that’s 0.72 C above the 20th Century average and about 1 C above 1890. For NASA, global temperatures also hit a similarly hot range. July of 2015 was 0.75 C above their 20th Century base line — putting it at about 0.95 C hotter than 1880s values when annual record keeping began. Now we only wait on NOAA’s report coming out in a few days for a final confirmation of this obscene July heat.
2015 On Track For Hottest Year By a Wide Margin
Focusing in on the NASA measure, we find that January through July temperatures are setting a course for a record shattering 2015. Overall, global temperatures during that seven month period were 0.8 C above NASA’s 20th Century benchmark and about 1 C above 1880s values. A level of heat that, if it were simply maintained, would beat out previous record hot year, 2014, by a substantial margin (0.07 C).
To the layman, these may seem like small numbers except when one considers that just 3.5 C of cooling from Holocene climates means the start of a new ice age. In just 135 years we’ve hit 30 percent of the difference between the Holocene and an ice age — but on the side of hot. Moreover, an annual temperature climb of 0.07 C equals 7 degrees Celsius warming if maintained for one Century. So a one year jump in that range is a pretty wide margin, especially when we consider that we’re now experiencing back-to-back hottest years on record.
El Nino + Climate Change In the NASA Graphic
(NASA’s July distribution of hot and cold temperature anomalies shows a world that’s tipping more and more toward climate extremes. Image source: NASA GISS.)
Geospatially, the representation of hot and cold temperature extremes in the NASA map hints at an absolute mess for July weather patterns. While abnormal and extreme warmth dominated the East Siberian, Chukchi, and Beaufort airs, a plug of below average temperatures hovered over the Laptev. Two substantial chimneys of heat extended into the Arctic — one exploding up from the Hot Blob in the Pacific and another stretching diagonally over the Lake Baikal region of Russia (Related: The Dry Land Burned Like Grass). Most of Western Europe baked while the Yamal region cooled. In the North Atlantic the Climate Change signature and storm generating cool pool maintained — gearing up to throw a few wicked cyclones at the British Isles in the midst of, what should be placid, summer.
And all across the equatorial region anomalous heat built — pushing monthly temperatures from 1-4 degrees Celsius above average in some of the typically hottest regions of the world. In this analysis we must pause for a moment to point out the awesome and terrible wave of heat building up from the Eastern Equatorial Pacific, telegraphing through the Hot Blobs off the North American West Coast and extending on up through the Bering Sea. A teleconnection feature that must fall if California is to have any hope of receiving a drought busting set of storms this Winter — monster El Nino or no.
The mid-to-equatorial latitudes of the Southern Hemisphere were also abnormally warm with few regions showing any departure into cooler than ‘normal’ in this zone. Meanwhile, the Southern Polar Region was a mess of hot ridges and cold troughs indicative of a very wavy Jet Stream pattern for the zone. In particular, a ridge blazing south through the Weddell Sea set off some much warmer than normal readings for Coats Land and the Ronne Ice Shelf.
(Zonal temperature anomalies for July show a clear signature of El Nino and a climate change related heat sink in the Southern Ocean. Image source: NASA GISS.)
In the NASA zonal map, we can clearly see the signature of El Nino. Equatorial temperatures are the hottest in the measure pushing to +1.3 degrees Celsius above average over the world’s belt-line. To the north, heat gradually tapered off — still maintaining near +1 C through the 40 degree line before dipping down to around +0.8 to +0.3 C in the 50s, 60s, and 70s and then rising again to around +0.7 C at the pole.
To the south, anomalies rapidly plunged throughout most zones — dipping to +0.35 C in the range of the furious fifties (50 degrees South Latitude). In the oceanic heat sink region where fresh and icy water met the warmer, saltier waters of the Southern Ocean, heat uptake by that ocean-atmosphere interface hit an extreme level as negative zonal anomalies spiked to -1.4 C in the range of 65 South Latitude. This ocean heat uptake and related atmospheric cooling is associated with a global warming related fresh water outflow due to Antarctic glacial melt — the Southern Hemisphere version of the North Atlantic cool pool. Zonal temperatures swing again higher, hitting +0.6 C at the land glacier edge in the region between 70 and 80 South, before dipping to around -0.7 C in the Antarctic interior near 90 South.
Conditions in Context
During the record hot July of 2015 temperature and weather hit new extremes. Variation between hot and cold temperatures became greater over many regions of the globe as hot and cool pools grew in prominence and related weather influence. Glacial melt and ocean current change related cool pools dominated the North Atlantic and a band near 70 South in the Southern Ocean. Meanwhile, extreme equatorial heat associated with El Nino developed teleconnections with high amplitude ridges — especially with the Hot Blob related Ridiculously Resilient Ridge over the Northeastern Pacific.
In addition, a synergy developed between high ocean temperatures, related high humidity, and a number of dangerous heatwaves. Near record and record hot waters in the regions of India, Pakistan, and Japan synergistically enabled deadly, mass-casualty producing heatwaves in those regions. This is due to the fact that hot waters enable higher wet bulb temperatures over land — pushing wet bulbs, at times, close to the human survival limit of 35 C.
With Global temperatures now at 1 C above 1880s levels we begin to witness hints of what a human-forced hothouse may look like. But what we see now are only the early, easy outliers.
(Please support public, non special interest based science, like the fantastic research produced by NASA and JMA without which this report would not have been possible.)