Arctic News: waves

Showing posts with label waves. Show all posts

Monday, July 10, 2017

Rain Over Arctic Ocean

It's raining over the Arctic Ocean and the rain is devastating the sea ice. What are the conditions that led to this?

As has been known for a long time, energy is added to Earth due to emissions by people and this translates into a warmer troposphere with more water vapor, warmer oceans and stronger winds.

Warming is hitting the Arctic particularly hard, due to numerous feedbacks, as illustrated by the sea surface temperature anomalies image on the right.

On July 6, 2017, cyclonic winds lined up to create a 'perfect storm'. As a result, an Atmospheric River of moisture was driven through Bering Strait into the Arctic Ocean, as shown on the images below.

On July 6, 2017, 1500 UTC, winds in Bering Strait were as high as 58 km/h (36 mph) at surface level (green circle on above image left), and as high as 82 km/h (51 mph) at 850 mb (green circle on above image right).

On July 6, 2017, surface temperatures of the air in Bering Strait were as high as 8.1°C (46.5°F) (green circle on image right).

Another indication of the strength of the wind driven through Bering Strait is wave height. On July 6, 2017, waves were as high as 3.35 m or 11 ft in the Bering Strait, at the location marked by the green circle on the image on the right.

The relatively warm and moist air driven through Bering Strait by strong winds is causing rain to fall over the sea ice of the Arctic Ocean, as shown on the video and images further below.

On July 7, 2017, high air temperatures were recorded over land and over the water.

The image below shows temperatures recorded at two locations over the Mackenzie River, one of 32.6°C or 90.8°F at the mouth of the Mackenzie River and another one of 34.7°C or 94.5°F further inland. Warm water from rivers can substantially warm up the sea surface and thus melt the sea ice.

Temperature of the surface of the water was 10°C or 50.1°F where the water was pushed into the Bering Strait, while temperatures as high as 46.9°C or 116.3°F were recorded over California.

The combined impact of high temperatures, strong winds, high waves and warm river water, rain water and melt water looks set to further devastate what sea ice is left in the Arctic Ocean.

Rain can be particularly devastating. The very force at which rain strikes can fracture the sea ice where it's weak, while pools of rainwater and meltwater will form at places where the sea ice is stronger. Where fractures appear in the sea ice, warm water can reach further parts of the ice and widen the cracks.

The video below shows rain over the Arctic Ocean. The video was created with cci-reorganizer.org forecasts from July 3, 2017, 18:00 UTC to July 17, 2017, 00:00 UTC.

Arctic sea ice is in a terrible shape. Sea ice volume is at a record low, as indicated by the Wipneus image below showing volume anomalies from 2002.

The image below, by Torstein Viddal, shows how low the 2017 year-to-date average sea ice volume is.

An additional danger is wildfires. Due to high temperatures, wildfires have broken out near the Mackenzie River, as illustrated by the satellite image below.

Wildfires come with a lot of emissions, including soot that darkens the surface when settling down, thus further speeding up warming.

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

Tuesday, June 6, 2017

High Waves Set To Batter Arctic Ocean

High temperatures hit Pakistan end May 2017. The image below shows readings as high as 51.1°C or 123.9°F on May 27, 2017 (at green circle).

As the image below shows, sea temperature was as high as 32.6°C or 90.6°F on May 28, 2017 (at the green circle), 1.8°C or 3.2°F warmer than 1981-2011.

High temperatures over land and at the sea surface reflect an atmosphere that contains huge amounts of energy. On May 28, 2017, the Convective Available Potential Energy (CAPE) reached levels as high as 7448 J/kg at the location in the United States marked by the green circle. Storms hit a large part of the United States, with baseball-sized hail reported on May 27, 2017.

Here's a link to a reported 56 °C (132 °F) temperature recorded in Iran and here's a link to an article describing a May 28, 2017, reading in Turbat, Pakistan, initially reported by the Pakistan Meteorological Department as 53.5°C (128.3°F) and later upgraded to 54.0°C (129.2°F.)

How could it be possible for growth of energy in the atmosphere to be accelerating, when CO₂ emissions from fossil fuels and industry (including cement production) have barely shown any recent growth, as discussed in an earlier post and as reported by EIA?

The image on the right depicts this possibility, while a recent post discussed the following scenario:

Warmer water tends to form a layer at the surface that does not mix well with the water underneath, as discussed before. Stratification reduces the capability of oceans to take up heat and CO₂ from the atmosphere. Less take-up by oceans of CO₂ will result in higher CO₂ levels in the atmosphere, further speeding up global warming.

Additionally, 93.4% of global warming currently goes into oceans. The more heat will remain in the atmosphere, the faster the temperature of the atmosphere will rise. This feedback can cause very rapid and strong global warming. as depicted on the image on the right and as also described as feedback #29 on the feedbacks page.

With this in mind, forecasts of storms hitting the Arctic Ocean over the next few months look even more frightening.

Waves as high as 2.34 m or 7.7 ft are forecast to hit the Arctic Ocean on June 8, 2017, at the location marked by the green circle.

How is it possible for waves to get that high in a part of the Arctic Ocean that is surrounded by continents that act as shields against winds?

On June 8, 2017, temperatures are forecast to be as high as 40.6°C or 105.2°F near Phoenix, Arizona, and as high as 26.0°C or 78.7°F in Alaska, as the image below shows.

The image below shows that on June 12, 2017, temperatures as high as 35.1°C or 95.3°F were recorded over a river in Siberia that ends in the Lena River which in turn ends in the Arctic Ocean (left panel, green circle), while waves near Novaya Zemlya were recorded as high as 4.54 m or 14.9 ft (top right panel, green circle).

The image below shows that on June 6, 2017, temperatures on the coast of Hudson Bay (green circle) were as high as 31.6°C or 89°F.

Four cyclones are visible on the above image. Strong winds over the Arctic Ocean can cause high waves that can break up the sea ice and strengthen currents that are pushing warm water into the Arctic Ocean and sea ice out of the Arctic Ocean.

Update: Above image shows that on June 18, 2017, 03:00 UTC, temperatures were as high as 29.5°C or 85°F over a Siberian river ending in the Arctic Ocean (green circle). Cyclones were making warm air flow into the Arctic Ocean. The forecast for June 25, 2017, on the right shows that this situation is likely to persist for another week.

These stronger winds, currents and waves come at a time that the Arctic sea ice thickness is at record low, as illustrated by the image below on the right by Wipneus and underneath by Larry Hamilton.

Let's take a closer look at some further feedbacks that are at work behind the increasingly thinner ice, higher temperature, stronger wind and higher waves in the Arctic.

• Sea Ice Decline - The snow and ice cover over the Arctic Ocean make that sunlight is reflected back into space (albedo loss). In the absence of this cover, the Arctic Ocean will absorb more heat. Furthermore, open oceans are less efficient than sea ice when it comes to emitting in the far-infrared region of the spectrum.

• Buffer Loss - The snow and ice cover over the Arctic Ocean acts as a buffer, absorbing heat that in the absence of this buffer will have to be absorbed by the Arctic Ocean, as discussed in earlier posts such as this one.

• Jet Stream Changes - Rising temperatures in the Arctic are causing wind patterns to change, in particular the jet stream.

As a result, warm air can more easily get carried by wind from land over the Arctic Ocean.

The image on the right shows the Jet Stream on June 6, 2017. As temperatures over the Arctic rise faster than they do at the Equator, the jet stream becomes more wavy.

[ click on images to enlarge ]

Instead of circumnavigating Earth in a straight and narrow band that keeps the cold air over the Arctic separate from warmer temperatures south of the jet stream, a more wavy jet stream enables more warm air to flow into the Arctic and more cold air to leave the Arctic.

Winds are particularly strong over oceans and, as the Atlantic Ocean keeps warming up, those winds can push more warm water into the Arctic Ocean, as discussed in an earlier post. This can dramatically warm up the water of the Arctic Ocean.

• Clouds and Water Vapor - Loops of the jet stream extending over the Arctic can also bring stronger winds and more clouds and water vapor into the Arctic.

[ forecast for jet stream, June 8, 2017 ]

This is another self-reinforcing feedback that goes hand in hand with the above feedbacks. As temperatures rise in the Arctic, loss of sea ice will increase, resulting in more open water. This, in combination with stronger winds and warmer water will also result in more clouds and water vapor over the Arctic, further speeding up the temperature rise in the Arctic.

• Decline of Snow and Ice Cover on Land - Rising temperatures in the Arctic are also speeding up the decline of the snow and ice cover on land. This will result in albedo loss and will also trigger further feedbacks, such as soil destabilization and warm water from rivers flowing into the Arctic Ocean.

• Soil destabilization - Heatwaves and droughts destabilize the soil. Soil that was previously known as permafrost, was until now held together by ice. As the ice melts, organic material in the soil starts to decompose and the soil becomes increasingly vulnerable to wildfires. All his can result in high emissions of CO₂, CH₄, N₂O, soot, etc., which in turn causes further warming, specifically over the Arctic. The danger of wildfires is illustrated by the image below.

• Warmer Rivers - High temperatures on land can strongly warm up water of rivers flowing into the Arctic Ocean. This is also illustrated by the above image.

• Seafloor Methane - Another huge dangers is that all this additional heat will reach the seafloor of the Arctic Ocean and will trigger destabilization of methane hydrates contained in sediments at the seafloor. Stronger winds can mix warmer water all the way down to the seafloor, and destabilize hydrates that can contain huge amounts of methane, resulting in release of huge quantities of methane into the atmosphere.

Meanwhile, an earthquake with a magnitude of 5.2 on the Richter scale hit the Greenland Sea, in between Greenland and Svalbard, on June 9, 2017 at 20:49:52 UTC at 79.931°N, 0.605°E and at 18.4 km depth. On June 12, 2017, methane levels as high as 2740 ppb were recorded, as the image below shows. While the image doesn't specify where these high levels occurred, the magenta-colored area near Greenland looks ominous, also because such high levels do not typically result from biological releases, but instead point at concentrated plumes such as can occur when clathrates get destabilized.

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

Links

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

• 10°C or 18°F warmer by 2021?
https://arctic-news.blogspot.com/2017/04/10c-or-18f-warmer-by-2021.html

• Abrupt Warming - How Much And How Fast?
https://arctic-news.blogspot.com/2017/05/abrupt-warming-how-much-and-how-fast.html

• Accelerating growth in CO₂ levels in the atmosphere
https//arctic-news.blogspot.com/2017/02/accelerating-growth-in-co2-levels-in-the-atmosphere.html

• Feedbacks
https://arctic-news.blogspot.com/p/feedbacks.html

• Warning of mass extinction of species, including humans, within one decade
https://arctic-news.blogspot.com/2017/02/warning-of-mass-extinction-of-species-including-humans-within-one-decade.html

Tuesday, December 8, 2015

Strong winds and High Waves hit Arctic Ocean

Strong winds and high waves are hitting the Arctic Ocean from both the Atlantic Ocean and the Pacific Ocean.

Above image shows waves as high as 12.36 m or 40.5 ft near Greenland on December 8, 2015.

The image on the right shows cyclonic winds with speeds as high as 142 km/h or 88 mph near Greenland on December 8, 2015.

The image further down on the right shows that waves as high as 14.04 m or 46.1 ft are forecast to hit the Aleutian Islands on December 13, 2015. Strong winds and high waves are forecast to subsequently keep moving in the direction of the Arctic Ocean.

The image below shows strong winds and high waves that are heading for Arctic Ocean, with waves as high as 17.18 m or 56.4 ft forecast to be moving toward the Arctic Ocean on December 13, 2015.

As warming continues, this situation can be expected to get worse, with extreme weather events hitting the Arctic Ocean with ever greater intensity.

The video below, created with Climate Reanalyzer images, shows strong winds over the period from December 5 to 15, 2015. The video illustrates how cyclonic winds are hitting the Arctic Ocean both from the Atlantic Ocean and the Pacific Ocean.

Such winds and waves can move a lot of warm water into the Arctic Ocean. There currently is only a very thin layer of sea ice present in the Bering Strait, which is prone to be broken up by strong waves. Moreover, warm water may move underneath the sea ice and cause warm water to mix down all the way to the seafloor, where it can destabilize sediments containing huge amounts of methane in the form of free gas and hydrates.

Furthermore, strong winds can dramatically speed up the currents that are moving sea ice out of the Arctic Ocean into the Atlantic Ocean. The Naval Research Laboratory animation below shows ice speed and drift, illustrating how strong winds are pushing huge amounts of sea ice out of the Arctic Ocean along the edge of Greenland into the Atlantic Ocean.

The Naval Research Laboratory animation below illustrates that the thicker sea ice has hardly grown recently, while large amounts of thick sea ice also get pushed out of the Arctic Ocean along the edge of Greenland into the Atlantic Ocean.

[ click on image to enlarge ]

The image on the right shows that, on December 11, 2015, sea surface temperature anomalies off the east coast of North America were as high as 18.1°F or 10.0°C compared to the daily average during years 1981-2011.

At the same time, the lid over the North Atlantic is expanding, due to heavy melting of glaciers and due to the large amounts of sea ice that are getting pushed out of the Arctic Ocean by strong winds. Expansion of the freshwater lid over the North Atlantic is cooling the sea surface of North Atlantic and is making the atmosphere over the North Atlantic cooler than it would be without this lid, as it makes that less heat gets transferred from ocean to atmosphere, as discussed in earlier posts such as this one.

The result is a widening difference in atmospheric temperature between the area off the east coast of North America and the North Atlantic. This widening difference causes stronger winds to flow to the North Atlantic, in turn causing more sea ice to be moved out the the Arctic Ocean and further speeding up this feedback (#28 at the feedbacks page).

The end result is that, due to this loss of sea ice occurring now, the sea ice will be in a very bad shape when the melting season starts again next year. Furthermore, this expanding lid on the North Atlantic will prevent heat transfer from ocean to atmosphere, resulting in warmer water arriving in the Arctic Ocean below the sea surface.

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

Waves as high as 12.36 m or 40.5 ft near Greenland on December 8, 2015. From the post 'Strong winds and High Waves hit...
Posted by Sam Carana on Tuesday, December 8, 2015

Sunday, March 15, 2015

Strong Winds And Waves Batter Arctic Sea Ice

As Earth warms, the intensity of storms is rising across the globe. At least eight people died in Vanuatu, as it was hit by Cyclone Pam. "It hit Port Vila at an incredible 340 kilometres an hour", mentions a recent news report. The left part of the image below shows Cyclone Pam reaching speeds as high as 144 kilometers an hour (89.48 mph, green circle) on March 12, 2015, 1500Z, while three further cyclones feature on the Southern Hemisphere.

At the same time, on the Northern Hemisphere, winds reached speeds as high as 101 km/h (62.76 mph, bottom green circle), 120 km/h (74.56 mph, middle green circle) and 112 km/h (69.59 mph, top green circle), as shown on the right part of above image.

The image on the right shows winds with speeds as high as 125 km/h (77.67 mph) batter the coast of Greenland on March 13, 2015 (green circle).

The image below shows strong winds moving from the North Atlantic into the Arctic Ocean on March 13, 2015.

The video below, with cci-reanalyzer.org forecasts for March 13 - 20, 2015, shows strong winds battering the Arctic Ocean at both the Pacific and Atlantic ends.

The combination image below shows winds around Greenland (top) and winds penetrating the Arctic Ocean (bottom).

Waves as high as 41.5 ft (12.65 m) were recorded between Svalbard and Norway on March 13, 2015 (green circle on the left part of the image below), while waves as high as 23.13 ft (7.05 m) were recorded close to the edge of the sea ice on March 15, 2015 (green circle on the right part of the image below).

The updated image below shows waves higher than 10 m (33 ft) near Svalbard close to the edge of the sea ice on March 16, 2015 (green circle).

Meanwhile, it more and more looks like the 2015 sea ice extent maximum was reached on February 25, as illustrated by the image below.

The image below (added later, ed.) shows Arctic sea ice area up to March 18, 2015 (top), and Arctic sea ice extent up to March 20, 2015 (bottom). Briefly, the difference between area and extent could be compared to Swiss cheese. Area is the cheese without the holes, while extent measures the cheese in addition to the holes. For more on this, see this NSIDC FAQ.

Strong winds can cause high waves that can break up the sea ice. At the same time, strong winds can speed up currents that push sea ice out of the Arctic Ocean, while bringing warmer water into the Arctic Ocean, as illustrated by the image below.

The image below shows sea surface temperatures of 20.9°C (69.62°F, green circle left) recorded off the coast of North America on March 14, 2015, an anomaly of 12.3°C or 26.54°F.

[ click on image to enlarge ]

The image below shows sea surface temperature anomalies in the Arctic Ocean on March 15, 2015.

The big danger is that warm water will trigger further releases of methane from the seafloor of the Arctic Ocean. Peak daily methane levels recorded in early 2015 averaged a very high 2370 parts per billion, as illustrated by the image below.

Natalia Shakhova et al. estimate the accumulated methane potential for the Eastern Siberian Arctic Shelf (ESAS, rectangle on image right) alone as follows:

- organic carbon in permafrost of about 500 Gt;
- about 1000 Gt in hydrate deposits; and
- about 700 Gt in free gas beneath the gas hydrate stability zone.

Hydrates can become destabilized by pressure changes that can be caused by earthquakes and resulting shockwaves and landslides, or that can be caused by wild temperature swings.

Hydrates can also become destabilized by a small temperature rise that can be caused by influx of warmer water from outside the Arctic Ocean or by warm surface water being mixed down by storms.

Waters in the ESAS are quite shallow, averaging less than 50 m depth over its 2x10ˆ6 km2 area, while methane hydrates in the ESAS can exist at depths as shallow as 20 m.

Where heat is able to penetrate the sediment along cracks, some hydrate destabilization can occur, which in turn can trigger larger destabilization, as methane escaping from a hydrate expands to 160 times its earlier volume; this explosive expansion can cause further destabilization of sediments containing methane in the form of hydrates and free gas.

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

Post by Sam Carana.

Tuesday, July 29, 2014

More than 2.5m Sea Level Rise by 2040?

A warming period more than 400,000 years ago pushed the Greenland ice sheet past its stability threshold (which may have been no more than several degrees above pre-industrial temperatures). This resulted in a nearly complete deglaciation of southern Greenland, raising global sea levels some 4.5-6 meters, found a recent study by Reyes et al. Due to melting elsewhere, global mean sea level then was 6 to 13 metres above the present level. Indeed, melting of the entire West Antarctic Ice Sheet can add a further 6-meter rise in sea levels. If the East Antarctic Ice Sheet (EAIS) were to melt as well, sea levels would rise by around 70 metres.

Sea level is now rising by 3.1mm (0.122 inch) per year. Much of this rise is due to rising temperatures, but there are also other factors. One quarter of the rise results from groundwater depletion, while run off from melting ice and glaciers adds another quarter and the remainder is attributed to thermal expansion of sea water. Furthermore, as temperatures rise, feedbacks start to kick in, e.g. the kinetic energy from stronger waves and more intense storms can speed things up.

Clearly, a rapid multi-meter rise would be devastating as it would flood many coastal cities, as well as much of the land now used to grow food. By how much have sea levels been rising recently and how fast can they be expected to rise in the near future?

NASA image, data by the JPL PODAAC, in support of the NASA's MEaSUREs program.

Sea levels have risen by some 60 mm over the past 20 years, as above NASA image shows, which has a linear trendline added. The question is whether a linear trendline is the most appropriate trendline, given that it suggests that a similar rise could be expected over the next 20 years. A polynomial trendline appears to fit the data better, as the animation below shows.

Such a polynomial trendline, however, points at a similar rise (of some 50 mm) in just four years time, with an even more steeper rise to follow, as illustrated by the image below.

And indeed, such a rise doesn't slow down there. A polynomial trendline applied to the data points at a sea level rise of more than 2.5 m (8.2 ft) by the year 2040.

The image below gives an idea of what a sea level rise of six feet (1.829 m) would do to the City of New York. Of course, this is only the sea level rise. Storm surge would come on top of this, as discussed at Ten Dangers of Global Warming.

So, what would be more appropriate, to expect sea levels to continue to rise in a linear way, or to take into account feedbacks that could speed things up? Where such feedbacks could lead to is illustrated by the image below.