Arctic News

Monday, January 22, 2018

2017 was hottest year on record

The year 2017 was the hottest year on record, as the image below illustrates.

When determining which year was the hottest year, care should be taken to avoid bias due to temporary conditions such as the El Niño that was present in 2016 and the La Niña we're now experiencing now. Above image uses NASA land+ocean January 2012-December 2017 anomalies from 1951-1980, adjusted by 0.59°C to cater for the rise from preindustrial to 1951-1980, to calculate a linear trend that goes some way to smooth out variability due to El Niño/La Niña events. The trend shows that 2017 was significantly warmer than 2016.

The trend also shows that 1.5°C above preindustrial was crossed back in 2016. This 1.5°C (or 2.7°F) was set at the Paris Agreement as a guardrail that was not to be crossed. The trend further shows that we've meanwhile crossed 1.6°C above preindustrial and we look set to cross the 2°C guardrail within years.

Global warming has crossed 1.5°C / 2.7°F above preindustrial and looks set to cross 2°C / 3.6°F soon. Due to accelerating warming in the Arctic, that could happen within one or two years time, i.e. much faster than the trendlines below may suggest.

Indeed, warming in the Arctic is taking place much faster than elsewhere, and the difference is accelerating. There's a huge danger that accelerating warming in the Arctic will speed up feedbacks such as:
• huge amounts of methane getting released from the seafloor of the Arctic Ocean;
• melting of sea ice and permafrost causing more sunlight to get absorbed in the Arctic, as less sunlight gets reflected back into space;
• changes to jet streams causing more extreme weather, in turn resulting in more emissions, such as due to wildfires;
• and more.

In conclusion, feedbacks could speed up global warming by much more than what may be suggested by above trends that look only at surface temperature of the atmosphere and that are based on previous data when such feedbacks had yet to become manifest.

Add up the impact of all warming elements and, as an earlier analysis shows, the rise in mean global temperatures from preindustrial could be more than 10°C in a matter of years, as illustrated by the image below, which shows a much steeper rise.

Particularly devastating feedbacks could result from changes regarding heat and carbon dioxide taken up by oceans. Oceans now take up 93.4% of global warming, as illustrated by the image below.

As said, when looking at surface temperatures of the atmosphere, there will be bias due to El Niño/La Niña events. One way to smooth out such bias is by calculating trendlines over many years. Another way to compensate for such bias is to also look at ocean heat. In terms of ocean heat, the year 2017 stands at the top, as the left panel of above image illustrates. In 2016, El Niño caused relatively more heat to be present in the atmosphere and less in oceans, whereas the opposite occurred in 2017, contributing to the fact that in 2017 a record amount of ocean heat was recorded. Occurrence of El Niño/La Niña events over the years is visualized by the image below.

One danger is that, in future, there will be more impact by El Niño events and less by La Niña events. A recent study concludes that as temperatures rise due to emissions by people, the frequency, magnitude and duration of strong El Niño events will increase.

In addition to higher temperature peaks due to El Niño events, more heat could remain in the atmosphere as the rise in temperature in general causes greater ocean stratification, making that less heat gets absorbed by oceans, as discussed in several earlier posts. The image below depicts this feedback and further feedbacks mentioned above. Feedbacks are described in more detail at the feedbacks page.

The situation is further illustrated by the danger assessment below.

[ Danger Assessment, from earlier post ]

Meanwhile, the Global Carbon Project projects a growth of 2% for the 2017 global carbon dioxide emissions from fossil fuels and industry (including cement production), compared to 2016 levels, as illustrated by image below.

Tuesday, January 2, 2018

Unfolding Arctic Catastrophe

On January 1, 2018, methane levels as high as 2764 ppb (parts per billion) were recorded. The solid magenta-colored areas near Greenland indicate that this very high reading was likely caused by methane hydrate destabilization in the sediments on the seafloor of the Arctic Ocean.

The state of the sea ice is behind this. On January 1, 2018, Arctic sea ice extent was at record low for the time of the year. The smaller the extent, the less sunlight gets reflected back into space and is instead absorbed in the Arctic.

At this time of year, though, hardly any sunshine is reaching the Arctic. So, what triggered this destabilization? As the image below indicates, year-to-date average Arctic sea ice volume has been at record low in 2017, which means that there has been very little sea ice underneath the surface throughout 2017.

Warm water will melt the sea ice from below, which keeps the water at greater depth cool. However, when there is little or no sea ice underneath the surface, little or no heat will be absorbed by the process of melting and the heat instead stays in the water, with the danger that it will reach sediments at the bottom of the Arctic Ocean, as illustrated by the image below.

The Buffer has gone, feedback #14 on the Feedbacks page

[ image from: Warming is accelerating ]

The image on the right shows warm water from the North Atlantic arriving near Svalbard. How warm is the water beneath the surface of the Arctic Ocean? The image below gives an indication, showing how much warmer the water was from October 1, 2017, to December 30, 2017, at selected areas near Svalbard, where warm water from the North Atlantic dives under the sea ice of the Arctic Ocean, carried by the Gulf Stream.

[ click on images to enlarge ]

In 1981-2011, temperatures were gradually falling by more than one degree Celsius from October 1 to the December 21 Solstice, then started to rise again in line with the change in seasons (blue line). In 2017, temperatures were rising in October. On October 25, 2017, the sea surface was as warm as 17.5°C or 63.5°F, i.e. a 14.1°C or 24.5°F anomaly. On average, it was 12.96°C or 23.35°F warmer during the period from October 1 to December 30, 2017 (red line), compared to the same days in 1981-2011.

The images below further illustrate the situation. Surface temperature of the atmosphere near Svalbard was as warm as 7°C or 44.5°F on January 13, 2018 (at green circle, left panel). The sea surface near Svalbard was as warm as 15.9°C or 60.8°F on January 12, 2018, compared to 2.4°C or 36.4°F on January 12 for the period 1981-2011 (at green circle, center panel). Waves as high as 13.04 m or 42.8 ft (at green circle, right panel) batter the North Atlantic along Norway's coast all the way to Svalbard on January 15, 2018.

The image below shows that waves as high as 16.01 m or 52.5 ft are forecast to batter the North Atlantic on January 16, 2018 (green circle, left panel). 100% relative humidity is recorded over the Arctic Ocean on January 15, 2018 (green circle, center panel). The Jet Stream reaches speeds as high as 426 km/h or 264 mph on January 15, 2018 (green circle, right panel).

Similar extreme weather patterns can be seen elsewhere in the Arctic. The image below on the left shows that temperatures as high as 18.5°C or 65.3°F were recorded on Jan. 14 and 15, 2018 in Metlakatla, Alaska. The image below on the right shows that surface temperatures as high as 7.4°C or 45.2°F were reached on January 16, 2018, in Yukon Territory, Canada (at green circle).

[ click on images to enlarge ]

Sunday, December 24, 2017

Winds keep changing as warming continues

November 2017 was 0.87 degrees Celsius warmer than the mean 1951-1980 November temperature, as above image shows. The last three Novembers — 2015, 2016, and 2017 — are the three warmest in the entire modern record. The warmest month of November happened in 2015 (+1.03°C) when there was a strong El Niño, while we're currently in a La Niña period.

On the image below, cyclonic winds on December 21, 2017, are visible near the Philippines and Vietnam. Near the Philippines, 3-hour precipitation accumulation was as high as 121.6 mm or 4.79 in (at green circle). As a BBC report describes, Tropical Storm Tembin made landfall in the southern Philippines on December 22, 2017, causing flash flooding and mudslides. More than 180 people are reported to have been killed, as the tropical storm swept through Mindanao island, with dozens more missing.

A week earlier, Tropical Storm Kai-Tak hit the central Philippines, killing dozens. The region is still recovering from Typhoon Haiyan, which killed more than 5,000 people and affected millions in 2013.

The winds are fueled by high sea surface temperatures. Above image shows that, on December 21, 2017, sea surface temperatures were as high as 31.7°C or 89°F north of Australia. In line with rising temperatures caused by global warming, sea surface temperature anomalies are high across the oceans, as the image below illustrates.

As above image also shows, the sea surface was relatively cold at locations indicative for El Niño (depicted as four El Niño regions on the right).

The image below shows El Niño forecast plumes indicating that we're currently in a La Niña period, and that temperatures are on the rise.

In conclusion, just like the rise in temperatures is currently masked by a La Niña period, the return to a new El Niño period will further strengthen the rise.

This strengthening of winds is what can be expected in a warmer world. Above image shows a wavy Northern Polar Jet Stream combine with the Northern Subtropical Jet Stream to reach speeds as high as 401 km/h or 249 mph.

As the jet stream becomes more wavy and extends over the Arctic, more warm air and water gets carried into the Arctic, further speeding up warming, as also discussed at The Arctic is changing the Jet Stream - Why This Is Important.

The importance of Arctic warming was also discussed in the recent post Warming is accelerating. Changes to the Jet Stream can cause a lot more heat to be brought into the Arctic, through both the Bering Strait and the Fram Strait. This image below shows wind through the Bering Strait reaching speeds as high as 135 km/h or 84 mph.

The combination image below shows the Jet Stream extending over the Arctic Ocean and remaining in place for days, reaching speeds as high as 206 km/h or 128 mph. Such 'blocking' patterns can cause a lot of heat to be brought into the Arctic atmosphere, as well as into the water of the Arctic Ocean. The image in the left-hand panel indicates that temperature anomalies over the Arctic Ocean could be as high as 30°C or 54°F.

[ click on images to enlarge ]

As the temperature difference between the North Pole and the Equator decreases, the Jet Stream becomes more wavy, at times extending deep over the continents and bringing cold air to the south. This further increases the (already high) temperature difference between land and ocean, further speeding up cyclonic winds that move over the oceans toward the North Pole and that carry warm water and air toward the Arctic Ocean. The image below shows a forecast for January 1, 2018.

As sea ice keeps declining, ever less sunlight gets reflected back into space. The image below shows the decline in global sea ice area over the years.

The image below shows the average year-to-date Arctic sea ice volume (PIOMAS data).

This further confirms the updated trend analysis of the NASA temperature anomaly below.

Sunday, December 17, 2017

Fires threaten Santa Barbara

New mandatory evacuation orders have been issued for the areas of Montecito, Summerland and some parts of Santa Barbara city, emergency officials said.

Above graph shows carbon monoxide (CO) and carbon dioxide (CO₂) levels from December 5 - 20, 2017, while the map below shows the location of the measurements (and forecasts).

The graph shows levels at one location and for one time of day (00:00 UTC for CO, respectively 01:30 UTC for CO₂). On December 11, 2017, at this location, but at 22:30 UTC, CO levels were 55639 ppb and CO₂ levels were 898 ppm, as illustrated the combination image below (left panel).

The right panel of the image below shows that CO₂ levels were as high as 922 ppm on December 7, 2017, at 01:30 UTC at a slightly different location. No CO₂ measurements were available for December 9 and 10, 2017, but given that levels of CO₂ and CO typically go up and down hand in hand, CO₂ may have peaked at well over 1000 ppm on December 9, 2017, possibly exceeding the 1229 ppm CO₂ measured in Montana on July 22, 2017.

Such fires look set to cause increasing amounts of emissions, speeding up warming of the atmosphere. These fires were fueled by extremely dry, hot and strong winds lasting for many days. Global warming is behind all these conditions. Not only does more heat translate into higher temperatures and stronger winds, the decreasing temperature difference between the Arctic and the Equator is also increasing the intensity and duration of more extreme weather events such as storms and droughts. A record 129 million trees on 8.9 million acres have died in California due to drought and bark beetles infestation.

“For the first time in history, on December 7th, the Cal Fire elevated the fire threat to purple for San Diego County, warning that the weather conditions presented an extreme risk of fire for San Diego,” California Governor Jerry Brown wrote in a request for federal emergency assistance. “Fire officials predict extreme winds of up to 80 miles per hour, equal to the wind speed of a category one hurricane.”

The following is an extract from the California Scoping Plan 2017:
“In California, as in the rest of the world, climate change is contributing to an escalation of serious problems, including raging wildfires, coastal erosion, disruption of water supply, threats to agriculture, spread of insect-borne diseases, and continuing health threats from air pollution. The drought that plagued California for years devastated the state’s agricultural and rural communities, leaving some of them with no drinking water at all. In 2015 alone, the drought cost agriculture in the Central Valley an estimated $2.7 billion, and more than 20,000 jobs. Last winter, the drought was broken by record-breaking rains, which led to flooding that tore through freeways, threatened rural communities, and isolated coastal areas. This year, California experienced the deadliest wildfires in its history. Climate change is making events like these more frequent, more catastrophic and more costly.”

The situation is dire and calls for comprehensive and effective action as described at the Climate Plan.

Links

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• Wildfires

https://arctic-news.blogspot.com/2017/07/wildfires.html

• Extreme weather is upon us