Showing posts with label speed. Show all posts
Showing posts with label speed. Show all posts

Monday, August 12, 2013

Cyclone raging on Thin Ice

Another cyclone is raging over the Arctic Ocean. The Naval Research Laboratory image below shows the speed and drift of the sea ice.

[ click on image to enlarge ]
Last time a cyclone hit the Arctic, this resulted in a temporary increase in area covered by sea ice, as shown on the Cryosphere Today image below. The cyclone pushed down on the sea ice, flattening it and pushing it sideways. 


Note that area as measured by the Cryosphere Today includes all spots that have a 15% or higher concentration of ice. This way of measuring area ignores the fact that the cyclone reduced the sea ice concentration in many spots, from a high sea ice concentration (around 90%) to a lower concentration (less than 80%), as shown on the Naval Research Laboratory image below. 


Furthermore, sea ice has since dropped in thickness, as illustrated by the Naval Research Laboratory image below. 

Much of the ice is now less than one meter thick, while some areas close to the North Pole have ice that is only between zero and half a meter thick.

The cyclone is raging most fiercely in those areas and much of the ice is drifting out into the Atlantic Ocean.

Neven mentioned at the Arctic Sea Ice Blog that average thickness (crudely calculated by dividing PIOMAS (PI) volume numbers with Cryosphere Today (CT) sea ice area numbers, see image below) had a very steep drop in July, similar to the drop in 2010. This year's trend line is now lowest, probably signifying that the ice pack is spread out and thin at the edges (read: melting potential).

[ click on image to enlarge ]
The image below, from the University of Bremen, Germany, shows sea ice concentration on August 11, 2013.



Wednesday, August 7, 2013

Another Arctic cyclone brewing

Another cyclone is brewing in the Arctic. Below are Naval Research Laboratory projections of sea ice drift a few days ahead.

[ click on image to enlarge ]
The image below, from Danmarks Meteorologiske Institut (DMI), shows surface pressure over the Arctic Ocean on August 7, 2013.

from: http://ocean.dmi.dk/arctic/weather/arcticweather.uk.php

Below are two projections of pressure and wind direction for August 11 and August 15, 2013.



edited screenshots from animation at weather-forecast.com
A further post with more details on this cyclone will be added soon.


Sunday, August 4, 2013

Methane as high as 2349 ppb


Earth is undergoing one of the largest climate changes in the past 65 million years, Stanford climate scientists Noah Diffenbaugh and Chris Field report, and it's on pace to occur at a rate 10 times faster than any change in that period.

“We know from past changes that ecosystems have responded to a few degrees of global temperature change over thousands of years,” said Diffenbaugh. “But the unprecedented trajectory that we're on now is forcing that change to occur over decades.”

Some of the strongest evidence for how the global climate system responds to high levels of carbon dioxide comes from paleoclimate studies. Fifty-five million years ago, carbon dioxide in the atmosphere was elevated to a level comparable to today. The Arctic Ocean did not have ice in the summer, and nearby land was warm enough to support alligators and palm trees. But apart from the rate of change, Diffenbaugh adds, another key difference is that “today there are multiple human stressors that were not present 55 million years ago, such as urbanization and air and water pollution.”

By the end of the century, should the current emissions of greenhouse gases remain unchecked, temperatures over the northern hemisphere will tip 5-6 degrees C warmer than today's averages. In this case, the hottest summer of the last 20 years becomes the new annual norm.

The situation looks to be even more dire than that, argues Sam Carana. In addition to carbon dioxide, there are further pollutants driving global warming. Moreover, as pictured below, feedbacks can dramatically accelerate the rise in temperature locally, particularly in the Arctic.

Image 21. For more details on feedbacks, see extended version of this image and discussion at

The level of methane in the atmosphere has already been rising even faster than the level of carbon dioxide, as illustrated by the image below. Moreover, there's the threat that large additional amounts of methane will suddenly be released, in particular from the Arctic seabed.


In August 2013, methane were recorded as high as 2349 ppb, as illustrated by the graph on below (added later, editor), showing that in early August, the world's mean methane level suddenly increased with at least 10 ppb compared to mean levels over the past few months.




To get an idea just how much methane has entered the atmosphere, have a look at the image below, covering several days from the start of August 2013.

[ click on image to enlarge ]


This is further illustrated by the two images below. The image directly below shows where the highest methane levels (i.e. over 1950 ppb, in yellow) were recorded on August 2, 2013.

[ click on image to enlarge ]
The image below shows the presence of methane on August 2, 2013, for a number of ranges, including at levels over 1950 ppb (this time in red).

[ click on image to enlarge ]
The methane threat is further described in the post Methane hydrates, which also features the image below.


Methane as high as 2303 ppb

This post has been updated as Methane as high as 2349 ppb.

Sunday, July 21, 2013

The Great Arctic Flush

By Paul Beckwith

A massive cyclone is forecast to develop in the Arctic, as shown on the image below, from the Naval Research Laboratory.

Within 2 weeks the Arctic Ocean will be completely transformed. The cyclone that appears 6 days out on both the US and European ten day forecasts will massacre the sea ice in what I call "The Great Arctic flush".

The image below is a forecast for Arctic sea ice speed and drift on July 27, 2013. More images, including animations, on Arctic sea ice can be viewed at http://www7320.nrlssc.navy.mil/hycomARC/arctic.html 


Last August, a massive cyclone formed over the Arctic Ocean and destroyed 800,000 square km of ice in about a week. The predicted cyclone looks to be as strong as the one in early August, 2012. Problem is, the ice is much weaker, thinner and fractured this year; including all the ice just north of the Canadian Arctic Archipelago that is 4 or 5 meters thick; this ice is mobile, broken, fractured ice piled up into ridges; it is not multiyear ice (MYI) at all.

Above image, from the Naval Research Laboratory is a prediction of ice speed and drift a week from now, showing the motion of the ice, the darker and redder the faster, the ice is being set in motion by the cyclone above. Since the Coriolis force flings things to the right, the ice is all sent to the outside of the rotation, into the warmer surrounding water as well as the Atlantic Ocean. The storm surge of a foot or two over the entire basin (highest near the cyclone eye) will draw in warm water from the Pacific via the Bering Strait and from the Atlantic via the Fram Strait. It will also mix the fresh water on the surface from melting ice with warmer saltier water from below. It will also generate lots of churning and grinding of the ice and waves several meters high. Warm and smoky air that is filled with ash and black carbon from burning fires in the far north will drop the albedo of the ice and increase the solar absorption. 

When I forecast zero sea ice at the end of the melt season this summer, I fully expected at least one or more of these massive cyclonic storms. Last year it occurred in early August, and lasted for about 8 days. In the rest of the melt season last year no other huge cyclone developed, although several small ones did. Perhaps the cyclone disturbed the ocean conditions enough to prevent subsequent ones occurring. We shall see this year...

edited screenshot from animation at weather-forecast.com


Paul Beckwith is a part-time professor with the laboratory for paleoclimatology and climatology, department of geography, University of Ottawa. He teaches second year climatology/meteorology. His PhD research topic is “Abrupt climate change in the past and present.” He holds an M.Sc. in laser physics and a B.Eng. in engineering physics and reached the rank of chess master in a previous life.

Friday, July 19, 2013

Arctic Ocean Events - Videos by Paul Beckwith

by Paul Beckwith


Massive Arctic cyclone effect on sea ice in August 2012
Part 1: August 1st to 16th, 2012
http://www.youtube.com/watch?v=nli47-9dT5o

Arctic sea ice motion (speed and direction) is compared to sea ice thickness from August 1st to August 16th, 2012. Sea ice motion is then compared to meteorology (500 mb pressure heights and 200 mb vector winds).




Massive Arctic cyclone effect on sea ice in August 2012
Part 2: August 1st to 16th, 2012
http://www.youtube.com/watch?v=WqwIVEpSg3w

Northern hemisphere meteorology (500mb pressure heights) and Arctic sea ice concentration compared to SST (sea surface temperatures) are examined from August 1st to August 16th, 2012 encompassing the mass persistent cyclone.




Massive Arctic cyclone effect on sea ice in August 2012
Part 3: August 1st to 16th, 2012
http://www.youtube.com/watch?v=HjYxRV0fzz4

Arctic basin SSS (sea surface salinity) is compared to SSH (sea surface height) during the period August 1st to August 16th, 2012 which encompassed a massive persistent cyclone. Detailed meteorology is also examined (tropopause temperature + pressure, surface precipitable water + pressure). Also examined is ocean profile salinity and temperature from an ice tethered buoy.




Massive Arctic cyclone effect on sea ice in August 2012
Part 4:  August 1st to 16th, 2012
http://www.youtube.com/watch?v=aAJRIV8YITY

The jet streams in the Arctic ocean basin are shown (200mb vector winds) from NOAA/ESRL daily data, as well as from 4 times daily data from SFSU. The data is given from August 1st to August 16th, 2012 which encompasses the massive Arctic cyclone.




2013

Arctic sea ice thickness + motion
May 14th to June 10th, 2013
http://www.youtube.com/watch?v=5ljHI0VITgk

Arctic sea ice data from May 14 to June 10, 2013
Left pane shows Arctic sea ice thickness; right pane shows sea ice motion (direction and speed).




Arctic sea ice thickness + motion
July 1st to 17th 2013
http://www.youtube.com/watch?v=cUZr51_yW5s

Arctic sea ice data from July 1st to July 17th, 2013. Left pane shows the Arctic sea ice thickness; right pane shows sea ice motion (direction and speed).




Sea ice concentration, temperature, salinity, and height;
July 1st to 18th, 2013
http://www.youtube.com/watch?v=icUtGqpkFx8

Arctic ocean data from US Navy for
1) sea ice concentration,
2) sea surface temperature (SST),
3) sea surface salinity (SSS), and
4) sea surface height (SSH)




Jet streams
July 1st to July 17th 2013
http://www.youtube.com/watch?v=IFbJCFVSiPI

Northern hemisphere (NH) jet streams are shown from two sources:
1) NOAA/ESRL data collected daily, and
2) SFSU data collect every 6 hours. Data is given for the time period from July 1st to July 17th, 2013.




Meteorology
July 1st to 18th 2013
http://www.youtube.com/watch?v=LONJT8JbM7I

The following meteorology plots are shown for time period July 1st to July 18th, 2013 over the Arctic Ocean between 60 degrees N and 90 degrees N:
1) 500mb pressure levels,
2) 200mb vector winds (jet streams),
3) precipitable water, and
4) tropopause temperatures.