As 2015 smashes temperature records, it's hotter than you think

by David Spratt

Spanish version

There is an El Niño in full swing which helps push average global temperatures higher, and records are being broken, but just how hot is it? For several years, we have heard that global warming has pushed temperatures higher by around 0.8 to 0.85 degrees Celsius (°C).

But in 2015, that number is not even close.

Even before this year's strong El Niño developed, 2015 was a hot year. The first few months of the year broken records for the hottest corresponding period in previous years all the way back to the start of the instrumental record in 1880. Each month, new records fell.



With the July data in, NOAA, the US Government's National Oceanic and Atmospheric Administration, reported that July was the hottest month among the 1627 months on record since 1880, and the first seven months of the year was the hottest January-July on record:

The July average temperature across global land and ocean surfaces was 0.81°C above the 20th century average. As July is climatologically the warmest month for the year, this was also the all-time highest monthly temperature in the 1880-2015 record, at 16.61°C, surpassing the previous record set in 1998 by 0.08°C.

The July globally-averaged sea surface temperature was 0.75°C above the 20th century average. This was the highest temperature for any month in the 1880-2015 record, surpassing the previous record set in July 2014 by 0.07°C. The global value was driven by record warmth across large expanses of the Pacific and Indian Oceans.

The year-to-date temperature combined across global land and ocean surfaces was 0.85°C above the 20th century average. This was the highest for January-July in the 1880-2015 record, surpassing the previous record set in 2010 by 0.09°C.

In addition the year-to-date globally-averaged land surface temperature beat the previous record in 2007 by a whopping 0.15°C, and the year-to-date globally-averaged sea surface temperature surpassed the previous record of 2010 by 0.06°C. Every major ocean basin observed record warmth in some areas.

And, as Joe Romm has reported, "It was especially hot for the 6 billion of us up here in the northern hemisphere, where the first seven months of 2015 were a remarkable 0.3°F (0.17°C) warmer than the first seven months of any year on record — and nearly a half degree Fahrenheit warmer than any year before 2007".

El Niño may be strongest on record

So this year, records are not being broken. They are being smashed, as a strong El Niño (and perhaps the strongest on record) is set to persist through to 2016. El Niño conditions are characterised by a warm band of water across the eastern tropical Pacific Ocean and facilitate the transfer of heat from the ocean surface layer to the atmosphere and are associated with a hotter climate.

The NOAA's most recent El Niño update (Climate Prediction Center / NCEP 17 August 2015) reports that:

All multi-model averages suggest that El Niño 3.4 will be above +1.5ºC (a “strong” El Niño) during late 2015 into early 2016.

(El Niño 3.4 is the zone of longitudes 120 to 150W along the equatorial Pacific Ocean).

As the chart above illustrates, the projected strength of the El Niño (yellow line) is slightly above the previous strongest such event in 1997 (red dots).

So hot will 2015 be? The NOAA has already reported that the first seven months of the year was almost 0.1°C above the previous record. This is a huge amount in a field where changes are often measured in one-hundredths of a degree.

With a 90% chance of the El Niño persisting into 2016, it is as close as a certain bet can be that 2015 will be the hottest year on the instrumental record.

And there is probably an even-money chance that the margin will exceed 0.1°C. This would be an incredible result with scientists shocked at the margin by which records are being broken. Former NASA climate science chief James Hansen says:

We can already predict that the 2015 global temperature will exceed the prior warmest year (2014) by an unusually wide margin (~ 0.1°C), exceeding 1998 (“El Niño of the century”) even further.

And there is a good chance that 2016 will beat 2015 to become the hottest year on record.

It's hotter than you think

But much hotter has it got already? The convention is to talk about the amount of warming "above pre-industrial", that is, before the steam-and-coal industrial revolution, around 1750.

But the instrumental record used by the major agencies in the US, the UK and Japan does not start till 1880, and it is this period that is often used to provide a "pre-industrial" baseline. So when we hear that warming so far up to (the average of) the last decade as being 0.8°C or 0.85°C, it is the warming from a 1880 baseline (see light green column in figure below of 0.87°C, based on the NOAA dataset since 1880).

But the climate around 1750 and 1880 were not the same. Research using proxy data and modelling shows that between 1750 and 1880 the global average temperature increased by ~0.2°C.

 When that is added (dark green column), we find that the real warming from pre-industrial 1750 to the average of the last decade is 1.07°C. It is a shock to see that we are more than half way to the unsafe 2°C "guardrail" favoured by international policy-makers.

The warming over 1750 pre-industrial to 2014 was 1.17°C.

And for the first seven months of 2015, the margin is a staggering 1.26°C higher than the pre-industrial level. Yes, it is a strong El Niño period, and it may drop back for a short while, but 2016 could be just as hot and we may be entering a new phase of accelerated warming.

Greenhouse emissions continue to soar to record levels, and attempts to clean up and retire some of the world's dirtiest coal power plants may result in a lowering of the production of aerosols (including black-carbon soot, organic carbon, sulphates, nitrates, as well as dust from smoke, manufacturing and windstorms) which at the moment provide a temporary (~1 week) cooling of 0.8-1°C.

The leading climate researcher Michael E. Mann says that as fossil fuel use is curtailed, the aerosol cooling impact will lessen. Mann says that "if the world burns significantly less coal…we would have to limit CO2 to below roughly 405 ppm", a level we will reach in two years.

A climate emergency requiring levels of action far beyond anything that is currently perceived by policy makers? As temperatures soar to record levels and it is hotter than most people understand, you can bet on that.

Earlier posted at ClimateCodeRed.org

As 2015 smashes temperature records, it's hotter than you think | by David Spratt http://arctic-news.blogspot.com/2015/09/as-2015-smashes-temperature-records-its-hotter-than-you-think.html

Posted by Sam Carana on Thursday, September 3, 2015

Arctic Sea Ice Collapse Threatens - Update 7

The image below shows Arctic sea ice extent, with the blue dot indicating that extent for August 30, 2015, was 4.804 million square kilometers. Satellite records shows that, at this time of the year, extent was only lower in 2007, 2011 and 2012.

There are a number of reasons why sea ice looks set to decrease dramatically over the next few weeks. On above image, extent for 2015 looks set to soon cross the lines for the years 2007 and 2011, while the sea ice today is in an even worse condition than one might conclude when looking at extent alone.

Thick sea ice is virtually absent compared to the situation in the year 2012 around this time of year, as illustrated by the image below that compares sea ice thickness on August 30, 2012 (left) with August 30, 2015 (right).

Furthermore, sea surface temperatures are very high. The North Pacific, on August 31, 2015, was about 1°C (1.8°F) warmer than it was compared to the period from 1971 to 2000, as illustrated by the Climate Reanalyzer image on the right.

As the image below shows, sea surface temperature anomalies are very high around North America, both in the Pacific Ocean and in the Atlantic Ocean.

The image below shows sea surface temperatures on August 30, 2015, indicating that a huge amount of ocean heat has accumulated in the Atlantic Ocean off the coast of North America.

The Gulf Stream is carrying much of this warm water toward the Arctic Ocean. Additionally, warm water from the Pacific Ocean is entering the Arctic Ocean through the Bering Strait.

Above image below shows sea surface temperature anomalies in the Arctic as at August 31, 2015.

There still are a few weeks to go before sea ice can be expected to reach its minimum, at around half September 2015, while sea currents will continue to carry warmer water into the Arctic Ocean for months to come.

There is a strengthening El Niño, while more open water increases the chance that storms will develop that will push the last remnants of the sea ice out of the Arctic Ocean, as discussed in earlier posts such as this one. Storms can also mix warm surface waters all the way down to the seafloor, as discussed in this earlier post. Typhoons increase this danger. The above image show three typhoons in the Pacific Ocean on 30 August, 2015, and the Climate Reanalyzer image on the right shows them on September 1, 2015.

These typhoons are headed in the direction of the Arctic. The Climate Reanalyzer forecast for September 8, 2015, below shows typhoons in the Pacific Ocean close to the Arctic Ocean, as well as strong wind over the Arctic Ocean.

The situation is dire and calls for comprehensive and effective action, as discussed in the Climate Plan.

Arctic Sea Ice Collapse Threatens - Update 6

The image below shows Arctic sea ice extent, with the blue dot indicating that extent for August 22, 2015, was 5.382 million square kilometers. The record shows that, at this time of the year, extent was only lower in 2007, 2011 and 2012.

There are a number of reasons why sea ice could fall dramatically over the next few weeks.

First of all, the situation today is in an even worse condition than one might conclude when looking at sea ice extent alone. The way NSIDC calculates extent is by first dividing the satellite image into a grid and then including each cell in extent that has 15% or more ice. So, if a few small and very thin pieces of ice floating in a cell happen to cover 15% of a cell, it is counted in as "sea ice".

There is quite a difference between the sea ice that was 5 meters thick north of Greenland in 2012 and the ice that is present there now. The image on the right shows the north-east corner of Greenland on the bottom left. There is almost no ice north of this point.

Thick sea ice is virtually absent compared to the situation in the year 2012 around this time of year, as illustrated by the image below that compares sea ice thickness on August 20, 2012 (left) with August 20, 2015 (right), from an earlier post.

Furthermore, sea surface temperatures are very high. The North Pacific, on August 23, 2015, was exactly 1°C (1.8°F) warmer than it was compared to the period from 1971 to 2000 (see Climate Reanalyzer image right).

As the image below shows, sea surface temperature anomalies are very high around North America. On August 23, 2015, sea surface temperature anomalies as high as 6.4°C (11.5°F) were recorded in the Bering Strait.

This is where warm waters from the Pacific Ocean are flowing into the Arctic Ocean.

The image below shows sea surface temperatures on August 22, 2015, indicating that a huge amount of ocean heat has accumulated in the Atlantic Ocean off the coast of North America.

The Gulf Stream is carrying much of this warm water toward the Arctic Ocean. On August 21, 2015, sea surface temperatures near Svalbard were as high as 17°C (62.6°F), a 12°C (21.5°F) anomaly, at the location marked by the green circle on the image below, showing sea surface temperatures in the top panel and sea surface temperature anomalies in the bottom panel.

The image below shows sea surface temperature anomalies in the Arctic as at August 23, 2015.

[ click on image to enlarge ]

There still are a few weeks to go before sea ice can be expected to reach its minimum, at around half September 2015, while sea currents will continue to carry warmer water into the Arctic Ocean for months to come.

More open water increases the chance that storms will develop that will push the last remnants of the sea ice out of the Arctic Ocean, as discussed in earlier posts such as this one, while storms can also mix warm surface waters all the way down to the seafloor, as discussed in this earlier post. The Climate Reanalyzer forecast for August 26, 2015, on the right shows strong winds both in the Bering Strait and the North Atlantic.

Typhoons increase this danger. The Climate Reanalyzer forecast for August 27, 2015, below shows a typhoon in the Pacific Ocean close to the Arctic Ocean.

The situation is dire and calls for comprehensive and effective action, as discussed in the Climate Plan.

On August 21, 2015, sea surface temperatures near Svalbard were as high as 17°C (62.6°F), a 12°C (21.5°F) anomaly, at...
Posted by Sam Carana on Monday, August 24, 2015

Ocean Heat Invades Arctic Ocean

[ click on image to enlarge ]

NOAA analysis shows that, on land, it now is about 1°C (1.8°F) warmer than the 20th century average.

July 2015 was the warmest month ever recorded for the globe. The combined average temperature over global land and ocean surfaces for July was the all-time highest monthly temperature in the 1880-2015 record – it was 16.61°C (61.86°F), i.e. 0.81°C (1.46°F) above the 20th century average. 

Sea surfaces were very warm as well, in particular the North Pacific, which on August 22, 2015, was exactly 1°C (1.8°F) warmer than it was compared to the period from 1971 to 2000 (see Climate Reanalyzer image right).

The July globally-averaged sea surface temperature was the highest temperature for any month in the 1880-2015 record. In July 2015, the sea surface on the Northern Hemisphere was 0.87°C (1.57°F) warmer than it was in the 20th century, as illustrated by the NOAA graph below. 

As the image below shows, the July data for sea surface temperature anomalies on the Northern Hemisphere contain a trendline pointing at a rise of 2°C (3.6°F) before the year 2030. In other words, if this trend continues, the sea surface will be 2°C (3.6°F) warmer in less than 15 years time from now.

[ click on image to enlarge ]

Such a temperature rise would be a catastrophe, as there are huge amounts of methane contained in the form of hydrates and free gas in sediments under the Arctic Ocean seafloor. A relatively small temperature rise of part of these sediments could cause a huge abrupt methane eruption, which could in turn trigger further eruptions of methane.

As illustrated by the image below, high methane levels are already showing up over the Arctic.

Methane levels as high as 2565 parts per billion were recorded on August 18, 2015

[ click on image to enlarge ]

Loss of Arctic sea ice could speed up such a development. The image on the right shows that, on August 20, 2015, Arctic sea ice extent was at a record low for the time of the year except for the years 2007, 2011 and 2012.

The situation today is even worse than one might conclude when looking at sea ice extent alone. Thick sea ice is virtually absent compared to the situation in the year 2012 around this time of year, as illustrated by the image below that compares sea ice thickness on August 20, 2012 (left) with August 20, 2015 (right).

The comparison below further illustrates this. The left panel shows how thick sea ice is anchored to the north-east tip of Greenland on July 7, 2015. The right panel shows how, on August 20, 2015, this ice has been fractured and shattered into pieces. All this ice looks set to soon flow down Fram Strait and melt away in ever warmer water.

The image below shows sea surface temperature anomalies on August 21, 2015.

On the image below, the green circle at the top of each globe indicates a location where sea surface temperature was 17°C (62.6°F) on August 21, 2015, an anomaly of 11.9°C (21.4°F). This is where warm water is entering the Arctic Ocean from the Atlantic Ocean. At the same time, warm water is entering the Arctic ocean through the Bering Strait from the Pacific Ocean.

[ click on image to enlarge ]

There still are a few weeks to go before sea ice can be expected to reach its minimum, at around half September 2015, while sea currents will continue to carry warmer water into the Arctic Ocean for months to come. More open water increases the chance that storms will develop that will push the last remnants of the sea ice out of the Arctic Ocean, as discussed in earlier posts such as this one, while storms can also mix warm surface waters all the way down to the seafloor, as discussed in this earlier post.

Typhoons increase this danger. The Climate Reanalyzer image below shows typhoons in the Pacific.

[ click on image to enlarge ]

Typhoons developing in the Pacific Ocean are getting stronger as the oceans warm. One of the typhoons visible on above map, Typhoon Goni, has just claimed ten lives in the Philippines.

Stronger typhoons come with an increased chance that they will bring strong winds and warm air and water into the Arctic.

Typhoon Goni and the larger Typhoon Atsani are both moving north and look set to move into the direction of the Arctic Ocean, as illustrated by the forecast for the situation on August 26, 2015, on the right.

Atsani was the twelfth typhoon and sixth super typhoon of the year in the western North Pacific—numbers that meteorologists say put the season on a record-breaking track. The NASA image below gives an idea of the size of Typhoon Atsani.

[ Typhoon Atsani - NASA image ]

The situation is dire and calls for comprehensive and effective action, as discussed in the Climate Plan.

July data for sea surface temperature anomalies on the Northern Hemisphere contain a trendline pointing at a rise of 2°C...
Posted by Sam Carana on Friday, August 21, 2015