Mauna Loa Methane Measure Shows Rising Rates of Increase Through End 2014

Mauna Loa Methane early December

(Atmospheric methane levels as measured at the Mauna Loa Observatory. Image source: NOAA/ESRL.)

Atmospheric methane levels as measured by the Mauna Loa Observatory (MLO) showed a continued steepening rate of increase through late 2014 — featuring one rather troubling spike late last month.

The measure, which has been recording atmospheric methane levels since the middle of the 20th Century, continued to ramp higher with readings hitting an average of 1850 parts per billion by late November.

Notably, this increase is at a faster pace than yearly averages for all of the last decade.

In addition, a single spike to 1910 parts per billion took place last month. This large departure of 60 parts per billion above the average was somewhat unusual for the Mauna Loa measure. The collection site is rather far from human or Arctic emissions sources which makes it less likely to feature anomalous spikes due to local influences. This particular spike also represents the largest single departure from the base line measure since 1984 (when the ESRL record begins).

Overall drivers of the more recent increase in global methane levels beginning around 2007 come from an increase in human emissions (likely due to rising rates of fossil fuel exploitation — primarily through hydrofracking and coal mining) as well as what appears to also be an increase in Arctic emissions. Large methane sources in Siberia, over the East Siberian Arctic Shelf, in the Laptev Sea, the Nares Strait, and west of Svalbard have been observed in both satellite monitors and through observations taken by scientists and researchers on the ground. Overall, a significant overburden of greenhouse gasses centers on the Arctic and appears to be enhanced by local carbon (methane and CO2) sources in the region.

More comprehensive measurements of methane releases over Alaska (according to NASA JPL), on the other hand, have not yet shown methane release departures above the global norm for land areas. But the observational record for Alaska composes just one year (2012), so there is no way to yet determine if permafrost carbon and methane releases from the tundra in that region increased to achieve their current rates. It is worth noting generally that the terrestrial zone for Alaska and its off shore region are not, as yet, major carbon release hot spots.

Global Warming Potential at Least 20 Times CO2

Methane (CH4) is an important greenhouse gas due to the fact that its global warming potential (GWP) over short periods is much higher when compared to a similar volume of CO2 (most measures consider the GWP of methane to be 20 times that of a similar volume of CO2). That said, methane’s residence time in the atmosphere is much shorter than CO2 and CO2 volumes are much larger. So CO2 is considered to be a more important gas when it comes to long term climate change. Nonetheless, CH4 increases since the start of the industrial revolution put it as the #2 gas now forcing the world to warm.

Very large outbursts of CH4 from the global carbon store (including terrestrial and ocean stores) during the Permian and PETM are hypothesized to have set off very rapid increases in global temperature. For some prominent researchers, this potential hazard is seen to be very low under current warming conditions. Others, however, seem very concerned that a rapid methane outburst under the very fast rate of human warming could be a tipping point we are fast approaching.

Observations in a Murky Scientific Context

It is important to note that the current profile of atmospheric methane increase does not yet look like one of catastrophic release. Instead, what we see is an overall ramping up of atmospheric levels.

The issue of catastrophic release potential — raised by Peter Wadhams, the Arctic Methane Emergency Group, and Dr. Simeletov and Shakhova among others — is not one that is certain or settled in the science.

As an example, Dr. Shakhova identifies a substantial but non-catastrophic 17 megaton atmospheric release from the East Siberian Arctic Shelf (equal to about 8 percent of the human emission and a substantial increase from a previous estimate of 8 megatons per year in 2010) as currently ongoing. However, both Simeletov and Shakhova have been the object of criticism due to their identification of a risk of a 3.5 gigaton per year methane release should all the East Siberian Arctic Shelf methane hot spots become active. Such a release would, in one year, nearly double the amount of all methane currently in the atmosphere (5 gigatons).

Dr. Peter Wadhams, another Arctic expert, has also received criticism for his assessment that a 50 gigaton release from the large subsea Arctic methane stores could be possible as sea ice retreat spurs Arctic Ocean sea floors to warm.

Other scientists such as GISS lead Gavin Schmidt and prominent Earth Systems modeler David Archer have noted that such very large releases aren’t currently likely. They point to natural traps that tend to tamp down sea based release rates (sometimes stopping as much as 90 percent of a destabilized methane source from hitting the atmosphere). They also note that current warming has probably not yet exceeded levels seen during the Eemian (130,000 years ago) and no large methane releases were observed at that time from Arctic carbon stores like the ESAS. They tend to take the view that any increasing rate of release coming from Arctic methane stores in particular and Arctic carbon stores in general will be very slow — so slow as to not be a significant amplifier of human warming (less than 5 percent) this century.

In general, between these two rather extreme and increasingly polarized views on Arctic methane, there appears to be very little in the way of middle ground. Although, a loosely related survey of permafrost carbon experts found a consensus opinion that the total carbon emission (including CO2 and methane) from land based tundra alone would equal between 10 and 35 percent of the current annual human emission by the end of this Century. It’s worth noting that this survey assessment does not include potential releases from the submerged permafrost in the ESAS or releases from other global carbon stores as a result of human warming.

The current rapid pace of human-caused warming — heating some regions of the Arctic as fast as 0.5 to 1 C per decade — also caused some of Archer and Schmidt’s scientific forebears, particularly James Hansen, to be rather less dismissive of the potential for a significant release from global methane stores, especially those in the Arctic. In any case, current human greenhouse gas emissions of nearly 50 gigatons CO2e each year are now in the process of pushing global temperatures past Eemian thresholds. An excession likely to elevate Anthropocene temperatures beyond all Eemian estimates before the mid 2030s under current rates of global greenhouse gas emissions and expected increases in fossil fuel burning.

So it is in this murky scientific context that we must interpret risks involving a continuing and apparently ramping rate of atmospheric methane increase. And what we can say with certainty is that there is little evidence that we are now hitting an exponential rise in global atmospheric methane levels. But that there is some evidence that a risk for such an event is real and requires much more detailed research and public dissemination of information to put what are some very valid concerns to rest.

Links:

NOAA ESRL

Alaska Methane Survey by JPL

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Warm Water Rising From the Depths: Much of Antarctica Now Under Threat of Melt

Antarctica. A seemingly impregnable fortress of cold. Ice mountains rising 2,100 meters high. Circumpolar winds raging out from this mass of chill frost walling the warm air out. And a curtain of sea ice insulating the surface air and mainland ice sheets from an increasingly warm world. A world that is now on track to experience one of its hottest years on record.

Antarctica, the coldest place on Earth, may well seem impregnable to this warming. But like any other fortress, it has its vulnerable spots. In this case, a weak underbelly. For in study after study, we keep finding evidence that warm waters are rising up from the abyss surrounding the chill and frozen continent. And the impact and risk to Antarctica’s glacial ice mountains is significant and growing.

Rapid Break-up of Ice From Filchner Ronne Ice Shelf in Jan 2010

(Collapse of ice structure at the leading edge of the Filchner-Ronne Ice Shelf adjacent to a rapidly warming Weddell Sea during January of 2010. A new study has found warm water upwelling from the Circumpolar Deep Water is rapidly approaching this massive ice shelf. Loss of Filchner-Ronne and its inland buttressed glaciers would result in 10 feet of sea level rise. Image source: Commons.)

For a study this week confirmed that Antarctica is now seeing a yearly loss of ice equal to one half the volume of Mt Everest every single year. A rate of loss triple that seen just ten years ago. An acceleration that, should it continue, means a much more immediate threat to coastal regions from sea level rise than current IPCC projections now estimate.

Shoaling of the Circumpolar Deep Water

The source of this warm water comes from a deep-running current that encircles all of Antarctica. Called the Circumpolar Deep Water, this current runs along the outside margin of the continental shelf. Lately, the current has been both warming and rising up the boundaries of the continental zone. And this combined action is rapidly bringing Antarctica’s great ice sheets under increasing threat of more rapid melt.

According to a new study led by Sunke Schmidtko, this deep water current has been warming at a rate of 0.1 degrees Celsius per decade since 1975. Even before this period of more rapid deep water warming, the current was already warmer than the continental shelf waters near Antarctica’s great glaciers. With the added warming, the Circumpolar Deep Water boasts temperatures in the range of 33 to 35 degrees Fahrenheit — enough heat to melt any glacier it contacts quite rapidly.

Out in the deep ocean waters beyond the continental shelf zone surrounding Antarctica, the now warmer waters of this current can do little to effect the great ice sheets. Here Sunke’s study identifies the crux of the problem — the waters of the Circumpolar Deep Water are surging up over the continental shelf margins to contact Antarctica’s sea fronting glaciers and ice shelves with increasing frequency.

In some cases, these warm waters have risen by more than 300 feet up the continental shelf margins and come into direct contact with Antarctic ice — causing it to rapidly melt. This process is most visible in the Amundsen Sea where an entire flank of West Antarctica is now found to be undergoing irreversible collapse. The great Pine Island Glacier, the Thwaites Glacier and many of its tributaries altogether composing enough ice to raise sea levels by 4 feet are now at the start of their last days. All due to an encroachment of warm water rising up from the abyss.

Rivers of Ice Antarctica

(Antarctic rivers of ice. Rising and warming waters from the Circumpolar Deep Water along continental margins have been increasingly coming into contact with ice shelf and glacier fronts that float upon or face the surrounding seas. The result has been much higher volumes of melt water contributions than expected from Antarctica. Image source: University of California.)

But the warm water rise is not just isolated to the Amundsen Sea. For Sunke also found that the warm water margin in the Weddell Sea on the opposite flank of West Antarctica was also rapidly on the rise. From 1980 to 2010, this warm water zone had risen from a depth of about 2100 feet to less than 1100 feet. A rapid advance toward another massive concentration of West Antarctic ice.

The impacts of a continued rise of this kind can best be described as chilling.

Sunke notes in an interview with National Geographic:

If this shoaling rate continues, there is a very high likelihood that the warm water will reach the Filchner Ronne Ice Shelf, with consequences which are huge.

Filchner Ronne, like the great Pine Island Glacier, has been calving larger and larger ice bergs during recent years. Should warm waters also destabilize this vast ice shelf another 1.5 feet of sea level rise would be locked in due to its direct loss. Including the massive inland glaciers that Filchner Ronne buttresses against a seaward surge, much larger than the ones near the Amundsen sea, would add a total of 10 feet worth of additional sea level rise.

Together, these destabilized zones would unleash much of West Antartica and some of Central Antartica, resulting in as much as 14 feet of sea level rise over a 100 to 200 year timeframe. This does not include Greenland, which is also undergoing rapid destabilization, nor does it include East Antarctica — which may also soon come under threat due to the encroachment of warm waters rising from the depths.

Are IPCC Projected Rates of Sea Level Rise Too Conservative?

The destabilization of glaciers along the Amundsen sea, the imminent threat to the Filchner Ronne Ice Shelf, and the less immediate but still troubling threat to East Antarctica’s glaciers, together with a rapidly destabilizing Greenland Ice Sheet, calls into question whether current IPCC predictions for sea level rise before 2100 are still valid.

IPCC projects a rise in seas of 1-3 feet by the end of this Century. But much of that rise is projected to come from thermal expansion of the world’s oceans — not from ice sheet melt in Antarctica and Greenland. Current rates of sea level rise of 3.3 milimeters each year would be enough to hit 1 foot of sea level rise by the end of this Century. However, just adding in the melting of the Filchner Ronne — a single large ice shelf — over the same period would add 4.4 milimeters a year. Add in a two century loss of the Amundsen glaciers — Pine Island and Thwaites — and we easily exceed the three foot mark by 2100.

Notably, this does not include the also increasingly rapid loss of ice coming from Greenland, the potential for mid century additions from East Antarctica, or lesser but still important additions from the world’s other melting glaciers.

Such more rapid losses to ice sheets may well reflect the realities of previous climates. At current CO2e levels of 481 ppm (400 ppm CO2 + Methane and other human greenhouse gas additions) global sea levels were as much as 75-120 feet higher than they are today. Predicted greenhouse gas levels of 550 to 600 ppm CO2e by the middle of this century (Breaking 550 ppm CO2 alone by 2050 to 2060) are enough to set in place conditions that would eventually melt all the ice on Earth and raise sea levels by more than 200 feet. For there was no time in the past 55 million years when large ice sheets existed under atmospheric CO2 concentrations exceeding 550 parts per million.

Glaciologist Eric Rignot has been warning for years that the IPCC sea level rise estimates may well be too conservative. And it seems that recent trends may well bear his warnings out. If so, the consequences to millions of people living along the world’s coastlines are stark and significant. For the world, it appears we face the increasing likelihood of a near-term inland mass-migration of people and property. A stunning set of losses and tragedy starting now and ongoing through many decades and centuries to come.

Links:

Warming Seas Drive Rapid Acceleration of Melting Antarctic Ice

Mass Loss of the Amundsen Sea Embayment of West Antarctica

Multidecadal Warming of Antarctic Waters

Research Casts Alarming Light on Decline of West Antarctic Glaciers

Antarctic Ice Shelf Being Eaten Away by Sea

Haiyan Redux? Monster Typhoon Hagupit Forecast To Strike Philippines Still Reeling From Last Year’s Terrible Blow

In early November of 2013 the monster Typhoon Haiyan roared ashore in the Central Philippines claiming over 8,000 souls and rendering many thousands more homeless. It was the strongest storm ever recorded on Earth over land — boasting winds exceeding 190 mph and pressures below 900 mb. It formed over ocean surface waters that were far warmer than normal and whose heat extended much further into the ocean depths than was typical. The kind of powerful storm that many atmospheric scientists say is more likely to occur as humans keep heating the ocean and atmosphere, providing fuel and conditions to make the most intense storms ever stronger.

Today, more than a year later, 15,000 people are still living in tents along a swath that saw more than 4 million homes destroyed as Haiyan made landfall. Climate and extreme weather refugees in a world that is, sadly, seeing more and more dislocated people. People affected by drought, water loss, and by the devastation of storms. From Syria to Brazil to California to the Philippines, the refrain is the same. Bad weather pushed people to the edge or over. It took their homes or made living where they are a nightmare.

And, for a Philippines still reeling from Haiyan’s brutal blow, it may just be happening again.

Hagupit

(December 4 infrared satellite shot of Hagupit as it approaches the central Philippines. Image source: NOAA MTSAT.)

As of yesterday afternoon Hagupit had bombed out into a category 5 monster storm boasting 1 minute sustained winds of 180 mph and a minimum central pressure of 905 mb. This put Hagupit in a tie with super typhoons Vongfong and Nuri as the strongest storms of 2014. Not quite as strong as Haiyan, but still a very dangerous storm. One strong enough to fling out 50 foot waves and bring a storm surge as tall as a two story house to Philippine shores.

Over the next few days Hagupit is expected to steadily weaken, roaring ashore in the Central Philippines as a strong Category 4 or weak Category 5 before slowly churning off toward the WNW toward Manila.

Hagupit is a gradual mover and covers a relatively broad area. The result is that tropical storm and intense typhoon conditions will persist over regions for longer periods than occurred with Haiyan, even if Hagupit is not quite as powerful. As mentioned above, of serious concern is that the currently predicted track of Hagupit will bring it near or over regions that have yet to fully recover from the terrible impacts of Haiyan.

Hagupit predicted track

(Predicted track and strength of Hagupit. Image source: Joint Typhoon Warning Center.)

Overall, the predicted track is a bit to the north of Haiyan’s shoreward surge of last year. However, the hardest hit areas are still uncomfortably close to the guidance cone. In addition, the current projected path features more flood prone coastal regions than Haiyan’s path. With many bay features to funnel in and amplify a storm surge.

Along this track, the storm would primarily be a major rainfall concern by the time it reached the capital city of Manila.

Climatology — Very Strong Supertyphoon in December Feature of a Globe in Hot Water

Climatologically, it’s a bit odd for such a strong storm to form in December, even in the warm Western Pacific (at peak intensity, Hagupit was the strongest December cyclone in at least the past 15 years). During recent years and under the apparent influence of a heating climate this region has tended to feature tropical cyclone formation year-round. A phenomena that some atmospheric scientists expect to continue to ramp up with human-caused warming.

sea surface temperature anomaly West Pacific

(Sea surface temperature anomaly for the Western Pacific in the vicinity of the Philippines. Image source: NOAA Sea Surface Temperature Anomaly Charts.)

Sea surface temperatures for the region remain in a very hot range of 0.5 to 2 degrees Celsius above the 20th Century average. Meanwhile, temperatures at depth are in the slightly above average range. So Hagupit has plenty of energy to feed on, even if conditions aren’t quite as favorable as they were for Haiyan last year.

Perhaps more striking is the persistence and intensity of ocean surface heat on both the regional and global levels. GFS models for the past 8 months have shown positive ocean surface anomalies in the range of +0.6 to +1.4 C above the 20th Century average. A very, very hot world ocean, especially when we consider that the typical major ocean heating event called El Nino was in neutral status throughout this period. In this context, it is also worth noting that January through October of 2014 was the hottest such period for the world surface in all of the 136 year global climate record. Again, occurring without the added heating influence of a declared El Nino.

The Western Pacific, itself, is the hottest ocean zone in the world. And high temperature departures there have been implicated both in increasing storminess at the surface and in a troubling heightening of the troposphere over a warm and warming region.

It is in this context that we should consider the extraordinary storms we’ve recently witnessed and the major potential impacts of Hagupit over the coming days.

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UPDATE: Thursday, Hagupit went through an eye replacement cycle as well as a brief period of weakening. This caused the storm to temporarily dip below super typhoon intensity (150 mph). As of Friday morning (EST), Hagupit had re-strengthened to a 150 mph monster storm with a very low central pressure of 915 mb.

A large and intense storm that is, at least one day ahead of landfall, already pushing seas to the steps of homes, washing out roads in the city of Samar where Hagupit is expected to make landfall, and lashing the Philippine coast with intense squalls.

It is worth noting that many communities in Samar and along the Philippine coast are low-lying and are thus very vulnerable to the effects of Hagupit. A fact the Philippine government appears well aware of as it has already evacuated more than 500,000 people ahead of landfall.

The storm will also race ashore over seas already elevated by human-caused climate change, though the peak of the warm water bulge has shifted east in a broader transition toward more El Nino-like conditions for the Equatorial Pacific.

Wind Shear — Limiting Storm Intensity

Hagupit is feeling the impacts of wind shear to its south and west and this influence is likely to keep the storm below the terrible intensities seen during Haiyan.

Hagupit SW wind shear

(Hagupit feeling the effects of southwest wind shear on December 5, 2014. Despite these influences, Hagupit is maintaining status as a strong category 4 storm. Image source: NOAA MTSAT.)

It is, nonetheless, predicted to be a very powerful storm — raking the Philippine Coast with category 4 winds (135-155 mph), monster waves, storm surges in excess of 10 feet and dumping 10-25 inches of rainfall over very broad regions. Areas along the path of the storm are likely to be heavily impacted by rainfall as the storm weakens and dumps copious moisture. The expected very heavy rainfall has also prompted lahar warnings for mudslides on the flanks of volcanos Mayan and Bulusan — both in Hagupit’s path.

Hagupit track

(Updated track of Hagupit from the Joint Typhoon Warning Center)

Hagupit’s current projected track brings its center about 50-100 miles north of Haiyan’s path. This predicted motion would spare regions hardest hit by Haiyan from Hagupit’s worst impacts. However, recent satellite imagery depicts a bit of a southward jog. This recent motion, combined with the storm’s broad size and slow forward speed, mean these regions may still take a substantial beating.

The storm is a slow mover — advancing only at a rate of 5-10 miles per hour. So regions will feel the impacts of Hagupit for much longer than Haiyan. For the Philippines as a whole, it looks like this will be a three day event. A longer duration storm, though somewhat less intense.

Links:

NOAA MTSAT

Joint Typhoon Warning Center

NOAA Sea Surface Temperature Anomaly Charts

More than 15,000 People Still Living in Tents a Year After Haiyan

Weather Underground (Who Is Matching Donations to a Charity Providing Relief for the Victims of Extreme Weather)

James Reynolds — Providing Live Updates From Samar on His Twitter Feed

Hat tip to Colorado Bob

(Post Edited on December 5)

Warm Arctic Winds Rip Polar Vortex in Half, Blast East Face of Greenland Ice Sheet

Last night, at around 9 PM Eastern Time, a broad region just south of the North Pole was undergoing an extraordinary warm-up. Temperatures along the 37 W Longitude line just 80 miles south of the pole had surged to 33 degrees Fahrenheit. A reading warmer than a region of central Michigan thousands of miles to the south but running over an area of sea ice more accustomed to -5 F or lower temperatures during the great dark of the December night.

image

(Knife of warm air drives above freezing temperatures to within 80 miles of the North Pole on December 1 of 2014. Image source: Earth Nullschool. Data Source: UCAR, OSCAR, NCEP.)

It was the much warmer than normal core of an intense and anomalous Arctic heat surge. One that blasted up over Svalbard and flooded into the high Arctic. Meeting with a similar but weaker air surge to the south, both surface and upper layers of the Arctic Ocean atmosphere hosted a joining of rivers of warm air.

This warm air double envelopment neatly sliced the polar vortex in twain. The remnant cold air cores at the Jet Stream level slipped down over both the Canadian Archipelago and Central Asia. Leaving open the lane for warm, maritime air to surge over the Arctic Ocean region.

image

(Jet Stream level atmospheric circulation shows polar vortex cut in two with one circulation over the Canadian Arctic Archipelago and the other over Yamal, Siberia — scene to the freakish methane blowholes earlier this year. Image source: Earth Nullschool. Data Source: UCAR, OSCAR, NCEP.)

It is a pattern of negative phase Arctic Oscillation (AO) — featuring a warming in the central Arctic which flushes the cold air out. But this ripping of the polar vortex in half is also related to polar amplification due to the human heat forcing. In which the high Arctic has warmed dramatically in comparison with the rest of the globe. So the heat anomalies we see now are much higher than they would otherwise be, with abnormal warmth remaining even into a positive phase of the AO (which we may see a bit more of, should El Nino finally emerge).

It’s a feature also related to a warming of the upper atmosphere at stratospheric levels. Such Sudden Stratospheric Warming (SSW) events can often be associated with the kind of polar vortex split we are seeing now. And, from recent observations, we find temperatures over the Arctic Stratosphere are now in record range.

According to weather blogger, Matthew Holliday:

Even though I wouldn’t categorize this as a *sudden* stratospheric event as of yet, the warming that has already occurred will likely have effects by middle December. In fact, the warming that has occurred is currently at record levels for this time of year.

Recent scientific studies have also indicated an increasing prevalence of SSW events as atmospheric carbon dioxide levels rise.

Extraordinary Arctic Warming

For much of November, readings in the Arctic as a whole have ranged from +1.5 to +2.5 degrees Celsius above the global average. A region featuring the highest global anomalies in a world that just saw its hottest ten months in the past 136 years, and probably its hottest ten months in many thousands of years. A region well known for its cold — but warming far faster than almost anywhere else.

Global anomaly Dec 1

(The Arctic hits an extraordinary early December +3.16 C positive anomaly on the first day of the month amidst a flood of warm air from the Atlantic and Pacific Oceans. Image source: The University of Maine. Data Source: Global Forecast System Model.)

Today, beset by this abnormal heat, overall Arctic departures hit 3.16 C above the already hotter than normal 1979 to 2000 average. Regions within this warm zone showed readings well above 36 F higher than average. A kind of winter Arctic heatwave. One that will keep worsening as the human heat forcing continues its terrible advance.

Near Freezing Temperatures Over Zachariae Glacier During Meteorological Winter

Much of the added heat expanded through the region between the North Pole and Greenland, wrapping in a surface circulation that has tended more and more to envelop the frozen isle, Baffin Bay and the accompanying Canadian Archipelago.

image

(Warm front off Atlantic Ocean featuring blow torch like wind flow over the Zahcariae Glacier collides with Greenland, pushes far into Arctic Ocean. Image source: Earth Nullschool. Data source: Data Source: UCAR, OSCAR, NCEP.)

This morning, some of that circulation and its entrapped warm air flow rode up over the East Coast of Greenland, surging over the ocean-facing cliffs of the Zachariae Glacier. Pushing temperatures to almost above freezing in a period where much deeper cold should be firmly established.

A great flood of abnormal winter warmth and moisture. The leading edge of a flow of ocean and atmospheric heat driven all too obviously by human warming.

Links:

UCAR

James Hansen: If It’s Warm, Why is it So Damned Cold?

Earth Nullschool

University of Maine

OSCAR

NCEP

Global Forecast System Model

National Climate Data Center

Changes in Northern Hemisphere Stratospheric Variability Under Increased CO2 Concentrations

Hat Tip to Wili

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