Arctic Sea Ice Extent Rapidly Decreasing Because of Climate Change; Weather & Climate Implications

Today, NOAA presented the State of the Arctic report at the American Geophysical Union annual conference in New Orleans. The news from the report was devastating for potential weather and climate impacts. Lots of important info to talk about from this! Let’s summarize:

  1. Annual Arctic sea ice extent is the lowest in 1600 years. This is based on proxy data (tree rings, lake sediments, ice cores from the Greenland Ice Sheet). There has been an abrupt decrease in extent during the 20th century (continuing to present). 24991395_10215050817330895_108575701643656859_n
  2. Arctic sea ice extent reached a record minimum in the warm season in 2012. However, 2015-17 witnessed consecutive record low maximum extents in the cold season. 2016 also had the lowest extent on record in November or December. 2017 is also witnessing top two or three low daily extents in November into December, with record low sea ice in the northern Bering Sea and the Chukchi Sea (north of the Bering Strait between Alaska and Russia). Also very notable, sea ice VOLUME (which includes thickness of ice) has continued to suffer with 2015-17 in the top 4 for the lowest volume on record going back to 1979 (and based on decreasing of sea ice extent and thickness, likely much much longer than that). Multi-year ice…ice more than a year old…is now nearly extinct in the Arctic Ocean.

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    Arctic Sea Ice Volume since 1979. Note consistent and accelerating collapse of sea ice volume. Arctic ice volume may fall below the 2012 record at some point in the month of September in the next several years.
  3. The Arctic had its warmest year on record in 2016 and its second warmest year on record in 2017 in reliable records. The climate of the Arctic is warming to the point that permafrost is increasingly melting releasing methane and carbon dioxide, methane emissions from what are called methane hydrates (methane gas locked in water ice) are increasing from the very shallow continental shelves surrounding the Arctic Ocean and mid-latitude weather patterns are becoming altered because of reduced sea ice (more on this shortly). The Arctic tundra is also greening at an increasing rate because of rapid warming.
  4. NOAA specifically states that “the Arctic shows no signs of returning to a reliably frozen region of recent decades” because of continued climate change related warming.

Discussion – Leaving the Ice Age Era:

One thing that we must remember about the sea ice of the Arctic Ocean (and the Southern Ocean around Antarctica) is that sea ice is a product of Ice Age eras. Our planet has had a tendency historically to flip between two global climate equilibrium states with dramatically different regional weather and seasonal patterns. The Ice Ages and the Hot House “Jurrasic Park” climates have been the two long-term dominating climate regimes in Earth’s history. One characterized by huge ice sheets and low sea levels, the other characterized by no ice sheets, no sea ice and high sea levels. Human civilization has flourished in the latest interglacial period in the Ice Age era because the climate has remained largely stable for roughly 10,000 years (-1 to +0.5 degrees C relative to mid-20th century climate) and mild enough to for extensive agriculture and settlements.

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Estimated temperature of Planet Earth from 550 million years ago to the end of the 20th century.

But now, because of Anthropogenic Global Warming (AGW) from climate change, we are leaving that stability in the geologic blink of an eye.

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Projected rise in global temperature of 4 degrees C/8 degrees F (relative to mid-20th century) during the 21st century relative to the past 10,000 years.

Probably the most important regulars of climate during Interglacials are the “refrigerators” of the north and south…the Arctic Ocean sea ice and Antarctic Ice Sheet (also Greenland Ice Sheet). However, as temperatures warm because of human carbon dioxide emissions trapping heat in the global climate system, that heat warms the atmosphere and ocean, attacking the sea ice by providing excess latent heat of melting. For the Arctic, this reduces the sea ice extent and volume decade after decade. Eventually, it will get to a point, where sea ice will become so thin and tenuous, it will undergo collapse to what has been called a “blue ocean” event with 1,000,000 sq km or less ice at a minimum in September (2012 extent minimum record was 3.41 million sq km). The 2016 and 2017 extent minimums were in the top 10 with 4.14 and 4.64 million sq km, 2nd and 8th respectively. 8 of the top 10 warm season minimum extents (in km) have occurred since 2010 in the now 39 year record. The Arctic Ocean and lower atmosphere are warming and becoming more like the high latitude North Atlantic. Eventually sea ice is expected to disappear completely in the warm season in the Arctic. Some climate scientists have suggested over the past several years that the “blue ocean” event resulting from a collapse of sea ice extent could occur between 2015-2020 or so as multi-year ice has nearly gone extinct, leaving thin ice vulnerable to quick melting and battering waves from cyclones. Computer models have been terrible at dealing with the end of sea ice in the Arctic, suggesting it would stick around into the second half of this century.

Discussion – Weather and Climate Implications:

So why does loss of sea ice matter? Sea ice regulates the climate of the world in multiple ways. It acts as large white surface which reflects most of the shortwave solar radiation from the sun (high albedo). As a result, it keeps the Arctic and Northern Hemisphere (and world) cooler than otherwise. It’s wide physical presence means heat entering the Arctic Ocean goes into melting the ice in the warm season (latent heat of melting; heat goes into phase change of water from solid to liquid) instead of heating the ocean and atmosphere dramatically (sensible heat to change temperature). Losing sea ice ends its presence as a climate regulator, allowing for more abrupt warming of the atmosphere-ocean system and increasing moisture content in the atmosphere (water vapor is an additional greenhouse gas; and increased clouds may reflect some radiation, but also can limit cooling in darkness). In addition, the Arctic Ocean will warm as it is a dark surface (low albedo). Increasing ocean warming in the marginal seas of the Arctic Ocean is already leading to increased methane emissions from the shallow continental shelves (as subsea permafrost thaw the clathrates) and more rapid warming will lead to an increase in emissions of methane and carbon dioxide from land permafrost (see discussion by Arctic climate scientist Dr. Peter Wadhams of Cambridge University on YouTube). Methane is over 100 times more powerful greenhouse gas than carbon dioxide on a timescale of several years (it dissipates far faster in the atmosphere, but sudden releases can increase warming quickly). And all of these feedbacks will much more quickly destroy the sea ice extent through further warming for a longer period in the warm season until ice disappears completely.

Increased warming of the Arctic also has impacts on mid-latitude weather. There has been research suggesting that the jet stream can be strongly influenced by Arctic warming and sea ice extent (see discussion by Dr. Jennifer Francis on YouTube). This can include a weakening of the upper-level jet stream which depends on the temperature difference between the upper-level mid-latitudes and polar atmosphere (known in meteorology as “baroclinic instability”). This weakening can lead to the jet stream developing high-amplitude waves more frequently, allowing for powerful upper-level ridges of high pressure to develop and cause blocking of the progressive westerly flow. This blocking can cause more frequent stagnant weather for locations, developing droughts in some areas through prolonged dryness, long periods of heavy precipitation in other regions as well as places of very abnormally warm temps (greater extreme summer heat) vs. colder temperatures (but the warmth always significantly outpaces the cold). Increased warming of the atmosphere in general also increases rainfall rates. In addition, paradoxically, while parts of the mid-latitudes may go through below normal temps and cold weather, the powerful ridging can produce extremely abnormally warm temperatures over the Arctic regions, intensifying the warming of the far north.

An identical pattern to this has largely set up over the Northern Hemisphere November into December.

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Powerful high-amplitude ridges over the Eastern Pacific and North Atlantic. Pattern relatively stagnant at this time.
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Reanalysis of the average temperature of Earth and specified regions over the last 30 days (1981-2010 baseline…add 0.7 C to compare to late 19th century). Note extensive, persistent anomalous warmth of the Arctic.

These effects may overall lead to more abrupt warming of the world as a whole as well as (more importantly) changes in rainfall and snowfall patterns, relevant for crops and food security from increasing summer extremes (heat stress and heavy rainfall) and water resources (snow pack, groundwater, etc). Also relevant for forest health (destruction by increasing wildfires as well as bug infestations killing hundreds of millions of trees in the Western US). And a running theme in stories on climate change recently? “Faster than expected” or “Faster than previously thought”. The importance of Arctic sea ice cannot be overstated and, unfortunately, this major tipping point…which I would consider a “keystone” tipping point because of what effects it can have down the line on other parts of the climate system…seems to be on the brink. It has been 2.6 million years since significant sea ice did not regularly exist in the warm season in the Arctic Ocean.

The statistics of weather has already changed significantly because of global warming with far more extreme heat events, drought periods and heavy precipitation events than in the mid-20th century (see presentation by Dr. Aaron Thierry on shift to more extreme weather conditions; starts 12:30 min, recommend watching through 20:30 min; also see discussion of climate change on increasing extreme events by Dr. Stefan Rahmstorf). Going past tipping points far earlier than expected by climate models will increase the likelihood for far more extreme weather events as weather patterns and circulations change (in some cases difficult to predict ways). Clearly, the world still needs adequate mitigation and adaptation measures to deal with these rapid and possibly abrupt changes.

For more info into how climate change influenced global extreme weather events in 2016, see the latest report (issued today) by the American Meteorological Society with attribution studies on last year’s significant events.

–Meteorologist Nick Humphrey

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The Realities of Progress on Climate Change Discussed at COP23

I found this discussion forum posted on YouTube with Dr. James Hansen and felt the need to share. Hansen is known as the “father of global warming awareness” since his testimony on the problem before Congress in the late 1980s and frequent contributions in both peer-reviewed literature and as a science communicator to the general public. This talk was posted just today from the latest international climate talks (Conference Of the Parties-23 or “COP-23” in Bonn, Germany) dealing with getting down details behind the Paris Climate Agreement signed the world’s nations in 2015 to try to limit global warming below 2 degrees C (3.6 degrees F) relative to 1750 and preferably below 1.5 C (2.7 F).

Here is the video (by user Nick Breeze who reports on Climate Change issues and interviews scientists…check out his YouTube Channel, good stuff)…audio isn’t the greatest but it is still highly recommended if you care about this important issue.

In this discussion, Hansen pretty much lays out a major problem. With all the talks over the years, nothing significant has been done to significantly reduce emissions of greenhouse gasses into Earth’s atmosphere. He points out something which other notable climate scientists have pointed out: We have run out of time as far as waiting on attempting to prevent “catastrophic warming” as far as impacts (those impacts really pick up intensity past 1.5 degrees C…we are currently around 1.1-1.2 C over the past few years) and while there are efforts to create alternative energy solutions and research carbon dioxide removal from the atmosphere, the only viable way he sees to get nations off of carbon is for govts to force the cost of fossil fuels to reflect the harm it causes to ecological and human health (pollution, climate change, etc). He’s spoken about how this could be done to put much of the money back in the pockets of Americans in the American political context (where the greatest monetary loss would likely be to the rich with a huge carbon footprint). But having the true ecological and human cost of fossil fuels…and not just the benefit in terms of driving the common economic drivers…be added to the cost would allow much greater competitiveness in the energy industry vs. now where fossil fuels are still by far the cheapest energy available for a variety of reasons (relative ease to extract, transport, existing technology vs. building new). And with oil companies influencing govts around the world, it makes it very hard to see realistic change outside of the pledges or changes which seem significant but in the end do little good on a global scale.

Example…current Paris Agreement pledges would cause the global warming to reach at least 3-4 degrees C (5.4-7.2 F) by the last decades of this century. And there are risks of unpredictable “positive feedbacks” (some known, some unknown) such as, severe chronic Arctic sea ice loss in the summer months, mass diebacks of tropical and boreal forests or methane release from (shallow) submerged continental shelf permafrost in the Arctic Ocean which would accelerate global warming even more. Methane…a short-lived but extremely powerful greenhouse gas…has already been observed releasing at increasing rates in the East Siberian Arctic Ocean and Laptev Sea because of increasing ocean warming. There is also simply the possibility that Earth overall is more sensitive to carbon dioxide than originally thought (actual scientific paper HERE).

I made this blog partly for informing people about the realities of climate change as it is ultimately we who must make sound decisions and force our governments to do the same. These conferences and agreements are great (and obviously I disagree with President Trump’s position on the issue), but optics cannot be the only thing which comes out of all these COPs. We must have an evolutionary change in how we conduct business on our only habitable planet. There are means to turn the tide…but the political will (and money) have to be invested in actually doing it.

–Meteorologist Nick Humphrey

Five Year Anniversary of Landfall of Superstorm Sandy

Five years ago today (October 29, 2012), the post-tropical remnants of what was Hurricane Sandy made landfall on the New Jersey coastline as a hurricane-force windstorm, causing destructive straight-line winds and historic, damaging surge from the North Atlantic extending from the Jersey coast north into the New York City Metro Area, with historic flooding of lower Manhattan.

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Image of extremely large Hurricane Sandy by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite on October 28, 2012. Sandy would become the largest tropical cyclone on record in the North Atlantic Basin.
Sandy produced widespread wind gusts of 75-90 mph across portions of New York and New Jersey with heavy rainfall totals of 7-10 inches across parts of New Jersey, Delaware, and Maryland. Storm surge was Sandy’s main cause of significant damage, with wind damage and flooding rainfall additional impacts. The post-tropical “superstorm” caused a 10-13 ft storm surge which damaged and destroyed homes and businesses along the Jersey Shore and Hudson Waterfront, with a record 13.88 ft water rise reported at Battery Park in Lower Manhattan.

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Damage by Super Storm Sandy in Brooklyn, NY (“Proud Novice” on Wikipedia).
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Super Storm Sandy damage in Mantoloking, NJ taken on October 30, 2012. (US Air Force).
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The flooded Brooklyn-Battery subway tunnel in NYC on October 30, 2012 (“vcohen” on Wikipedia).
Sandy’s expansive storm surge was more intense by multiple factors. As it came poleward, it grew significantly in size, a typical phenomenon for tropical cyclones moving into the mid-latitudes. However, Sandy’s weakening and mid-latitude interactions caused it become the largest North Atlantic tropical cyclone on record, producing a huge fetch (extensive wind over long stretch of open water). This fetch allowed for the building of significant ocean waves and piling up of water toward the shallow continental shelf of the Atlantic coast of the US. And although Sandy weakened somewhat and became “non-tropical”, this did not matter as the very large wind field remained and forward momentum of the very heavy ocean could not settle down in time before pounding the coastline with destructive surge.

In addition, Sandy made landfall at high tide, enhancing the storm’s ability to flood dry land areas and cause direct damage with battering waves. I will also note that this “flood reach” was even greater because of climate change-induced sea level rise. Global sea levels have risen 9 inches since 1880 and while the Intergovernmental Panel on Climate Change (UN) continues to indicate a likely sea level rise of up to 3.2 ft by 2100, many other reputable scientists have suggested the possibility of multi-foot sea level rise occurring this century as the result of exponential glacial melt feedbacks in Greenland and Antarctica. Perhaps as high as 6.5-16.5 feet by 2100 (see references #1-2 below). This, of course would be catastrophic for vulnerable coastal cities for both livability but initially for any places already exposed to storm surges. New York City is one most at risk.


Sea level rise has also been locally enhanced along the Northeast US Coast because of abnormally warm waters building offshore for years, leading to increased thermal expansion of the water surface upward. This may also be a result of climate change-induced weakening (#3) of the Atlantic Meridional Overturning Circulation (AMOC). While Superstorm Sandy wasn’t “caused” by climate change, it was part of an increasing regime of more extreme weather events (and events with with more extreme hazard variables) and a prelude to what will be far more frequent in the coming decades.

Sandy was retired after the 2012 Hurricane Season, causing 233 deaths from the Caribbean to the United States and producing an incredible $75 billion in damages (only 2nd to Hurricane Katrina). An incredible and devastating meteorological event which we can hope we continue to recover from and our country will be better prepared to mitigate against next time.

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Surface analysis at 5 pm EDT October 29, 2012 showing Superstorm Sandy just offshore the coast of New Jersey pounding the Mid-Atlantic to New England. The intense pressure gradient (shown by the isobars) caused areas of gale and storm force winds over the Great Lakes because of the expanse of the storm.
Scientific References (for the nerds like me!):

1- Hansen et al. 2016. (scientific technical)

2- New science suggests the ocean could rise more — and faster — than we thought (Washington Post/Oct 17)

3. Youtube video of conference presentation (2016) by Dr. Stefan Rahmstorf on weakening AMOC. Can also refer to (#1) on this issue as it relates to potential effect on ice sheet dynamics.

My view of the August 21, 2017 Total Eclipse.

 

What an amazing event! The moon’s shadow gave a big show across America today and at 1:02 pm CDT it rushed over Lincoln, NE at over 1500 mph. Day turned to night, the temperature dropped and a 360 degree twilight ruled the midday.

First…my video!

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Screen capture from video during totality in Lincoln, NE. Shows the “eclipse twilight” surrounding the city. Photo by me (Nick Humphrey).

The temperature in Lincoln dropped from 81 degrees around noon to 77 degrees after 1 pm and totality. Many locations along the eclipse path experienced temperature falls of 3-5 degrees as a result of the passage of the Moon’s shadow. Meteorologists also observed (both on the ground and with satellite imagery) the collapse of convective cumulus clouds dependent upon surface heating to “bubble”, which was lost during the advanced partial and total eclipses.

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Cumulus cloud field impacted by the eclipse. Cloud field (12:42 pm CDT) dissipates by 2:32 pm CDT as totality approaches. Photo courtesy of AccuWeather Meteorologist Becky DePodwin. Lowering of temperature weakens upward convection currents likely limiting maintenance of cumulus clouds and leading to their dissipation in the absence of other lifting mechanisms.

You can watch the progression of the Moon’s shadow across North America below (video is only four seconds long so you’ll have to replay to see it more than once at a time):

All I can say is that this was one of most spectacular events of nature I’ve ever witnessed. I’ve witnessed multiple total lunar eclipses and while they are spooky (especially in the middle of the night), nothing can beat the powerful changes which a total solar eclipse can bring to the landscape.

The clouds, which were the most problematic for eclipse viewing in Nebraska ended up breaking enough to see totality itself, but also provided a canvas for the incredible glow of midday twilight. It was quite magical.

The next total solar eclipse in the Lower 48 is April 8, 2024. Totality in parts of Texas (which will include Austin and Dallas/Fort Worth Metro) could last nearly 4 1/2 min compared to the 2 min 40 sec max with today’s eclipse. If time and finances align, I definitely want travel for that one if I don’t live near it by then.

Anyone have any eclipse experiences they want to share? I’ll be checking out WordPress posts too! 🙂

PS-A view from a Omaha news station of the twilight colors with clouds HERE (video) within totality near Beatrice, NE, south of Lincoln.