Sun. Aug 19th, 2018

Variable week – Thursday Thunder – The Arctic Breaks up Fast and Early

  • Vancouver Island Inland Sections Forecast - SPECIAL AIR QUALITY STATEMENT IN EFFECT
    Issued: 9:16 PM PDT Saturday 18 August 2018

    Forecast Issued 4:00 PM PDT Saturday 18 August 2018 - Saturday night: Clear. Local smoke. Low 11. Sunday: Sunny. Local smoke. High 33. Humidex 36. UV index 7 or high. Sunday night: Clear. Local smoke. Low 12. Monday: Sunny. High 34. Monday night: Clear. Low 12. Tuesday: Sunny. High 34. Tuesday night: Clear. Low 13. Wednesday: Sunny. High 24. Wednesday night: Cloudy periods. Low 14. Thursday: Cloudy with 60 percent chance of showers. High 21. Thursday night: Cloudy periods. Low 13. Friday: A mix of sun and cloud. High 20.

  • Current Conditions
    Temperature
    19.4° C
    -0.9 ° C/hr
    Barometer
    101.9 kPa
    0.0
    Wind
    N/A 0.0 km/h
    gusting 0.0 km/h
    Humidity
    66 %
    Rain Rate
    0.0 mm/hr
    Wind Chill
    19.4° C
    Heat Index
    19.4° C
    Dewpoint
    12.9° C
    UV
    0.0
    Solar
    0 W/m2
    Last Updated: 22:55:00 PDT
    Click to Refresh or See All Conditions
  • Day Almanac
    Day's Rain
    0.0 mm
    Day ET
    0.0 mm mm
    Rain Storm
    NotAvailable mm
    Civil Rise
    05:39
    Moon Phase
    First quarter (59% full)
    Civil Set
    21:05
    Day Length
    13:22:59
    Day High
    29.8° C @ 15:23 Tdy.
    Day Low
    11.7° C @ 06:30 Tdy.
    Day High Rain Rate
    0.0mm/hr00:00
    Day High Barometer
    102.42 kPa @ 07:58 Tdy.
    Day Low Barometer
    101.79 kPa @ 19:44 Tdy.
    Day Low Windchill
    11.7° C @ 06:30 Tdy.
    Day High Heat Index
    29.8° C @ 15:23 Tdy.
    Day High Wind Gust
    S 16.3km/h @ 16:05 Tdy.
    Day High Solar Radiation
    1220W/m2 @ 13:26 Tdy.
    Day High UV Index
    7.8 @ 13:25 Tdy.

It will be mostly cloudy and dry this week but it should stay pleasantly warm.  We should get some sunny breaks this afternoon and then back to cloud Wednesday.

On Thursday things get a little more interesting as there appears to be a chance for some thunderstorms in the afternoon.

The first indication is afternoon rain on the model:

wa_pcp3.75.0000

Then looking at the vertical velocity (the atmosphere moving up and down) shows increased activity at the same time:

700w.72.0000

When you see red and blue directly beside each other that is a good sign of convection in a thunderstorm.

And finally, the model prediction for actual Convective Potential.

lightning2.72.0000

Shows some dots of activity on the Alberni Inlet and in between the Alberni and Comox Valley.

So we should be prepared for that.  This could also trigger some wildfire activity as well.  The current wildfire rating is Moderate though it is forecast to increase to High today and tomorrow.  It is nice to see no wildfire activity currently on the Island after the long weekend.

Screen Shot 2016-05-24 at 7.43.45 AM Screen Shot 2016-05-24 at 7.44.08 AM

Early Arctic Breakup gives potential for record low

When I’ve had time I’ve been trying to keep an eye on what has been happening in the Arctic this year.  Why?  Well certainly one reason is because the Arctic is the fastest warming place on earth when it comes to climate change/global warming and those rapid changes are being linked as drivers for other changes like a slowing, super wavy jet stream, the blob, and early onset of drought causing increased Peace River and Alberta fire activity including around Fort Mac.

From “the blob” link above:

In September 2012, after massive cyclones, there was the lowest sea ice pack ever recorded in the Arctic and, with more ocean exposed, heat was absorbed into the Arctic Ocean.

It delayed the freezing of the Arctic. The Arctic vortex was very weak and small, so there was no northern boundary to the jet stream and [that allows] the jet stream to go into huge meanders,” Dewey said.

And a wandering jet stream means wacky weather.

The Blob is not driving the weather, the weather is driving The Blob,” Dewey said.

The implication is that meandering allowed for the Aleutian Lows that normally spin in the NE Pacific to be taken further north, and thus more calm, air to sit there instead, heating the ocean and creating a great repository of heat.

So now, we come to this year’s Arctic sea ice situation:

First a look at the current graph for sea ice coverage.  We can see it is tracking quite a bit below previous years including the year of the last record low in 2012.

icecover_current_new

The primary focus has been on the Beaufort region above Alaska, Yukon and the North West Territories.

NASA released this comparison a few days ago of the breakup in April over the past 3 years.

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I went to the EOSDIS Worldview webpage for the TERRA Satellite that shows high resolution imagery of the globe.  The orientations of the satellite camera changed over time so I put a star in the same location on each image so you can get your bearings.  The scales are the same.

Here is a shot from May 23, 2012:

Screen Shot 2016-05-24 at 8.20.25 AM

And here is one from Yesterday (May 23, 2016)

Screen Shot 2016-05-24 at 8.19.17 AM

You can see the ice has nearly completely melted from the coast this year compared to 2012 when there was still a significant shelf at this time.  The ice that is there looks just as fractured and broken up in 2012 and as it is in 2016.

Of course, this is just one part of the Arctic so what does the picture for the whole Arctic look like?

My favourite animation is from the US Navy thickness chart.  Here is the month of May so far.  Notice the lower area of the Beaufort clearing out.  Also notice the general clockwise rotation in that area. That is known as the Beaufort Gyre.

arcticictn_nowcast_anim30d

Also notice the very small sliver of black at the top of the Canadian Archipelago and the general lack of yellow and reds of thicker ice.

Now check out the same month of May (up to the 23rd) in 2012:

www.GIFCreator.me_far8Ey

Now you should see the dramatic difference.  Even though 2012 ended up the lower sea ice cover in September ever recorded, it started, at this time of year, with far more old, thick ice than we have this year.

This is obviously a concern and an indicator of a potential new low. Whether that happens will be determined by the immediate weather over the next few months.  If it is unusually cloudy and cool, the decline might level off.  If it is abnormally clear and warm, then watch out.  We could be in for a new record come September.  And that will have implications for our weather down here on Vancouver Island.