Lubricated earthquakes

It’s well known that tectonic plates can slip underneath another plate in subduction zones and that violent earthquakes occur when the plates stick and release. Research is revealing the frequency of potential earthquakes. If it weren’t for ‘lubricated’ sliding, British Columbia would have a major earthquake every fourteen months and Japan every six. I’m not sure whether the lubrication is from melting rock or from seawater or a bit of both.

 

A map of British Columbia's seacoast shows where earthquakes occur

Cascadia subduction zone

Neanderthals evolved greater intelligence independently

A rare find of Neanderthal fossils or subfossils shows that early Neanderthals were small-brained and developed larger brains independently of the line that led to us.

As best we can tell, humans and Neanderthals diverged from a common ancestor about 500,000 years ago, a species called Homo heidelbergenesis. Modern humans appeared in Africa some 300,000 years later, a time when Neanderthals were already romping around Europe and Asia.

These skulls are 430,000 years old. They have a small  braincase but in other respects have Neanderthal characteristics.

…the Neanderthal trait of an elongated and rounded brain case came later.

Invasive species old and new

The Winnipeg Free Press reports on six species that have moved out of their home grounds and become a nuisance in Canada or the U.S., doing ecological damage: the Asian carp, the American bullfrog, Burmese python, killer bees, zebra mussels, and purple loosestrife.

Mammograms: when and how often?

At what age should we start getting mammograms and how often should we get them? It’s necessary to balance the dangers of ionizing radiation against the benefits of detecting cancer early. Read “Mammography’s Limits are Becoming Clear.”

“Stars hung suspended” — robot camera finds ice-dwelling anemones

A robot camera in the Antarctic Ocean found something that no one was looking for: bloodless sea anemones anchored to the underside of the Ross Ice Shelf. The researchers, from the University of Nebraska, dropped their camera-robot through the 270-metre-thick ice to explore sea currents and test their machine. The team did not include any biologists but they preserved some of the tiny animals for later study. These are the first anemones found that live in or on ice: ANDRILL team discovers ice-loving sea anemones in Antarctica. They are only a couple of centimetres high.

“The white anemones have been named Edwardsiella andrillae, in honor of the ANDRILL program.” I guess we’ll have to look at PLoS One to discover why they were placed in Edwardsiella so quickly. (the anemones, not the bacteria): Edwardsiella andrillae, a New Species of Sea Anemone from Antarctic Ice.

The large-scale image of the discovery is stunning.

Ice-dwelling anemones

Weather alert for Toronto, 5 January 2014

When I checked the weather alerts, I found that our ‘special weather statement’ has been updated to a warning.

City of Toronto
4:51 PM EST Sunday 05 January 2014
Freezing rain warning
for City of Toronto continued

A couple of hours of freezing rain likely north of lakes Erie and Ontario this evening. Significant freezing rain over Eastern Ontario overnight. Risk of a flash freeze for rush hour Monday morning.

An intensifying storm centred over Southern Indiana is forecast to cross the Greater Toronto area overnight reaching Petawawa Monday morning. Heavier snow is beginning to develop across parts of Southern Ontario in advance of the low. It will quickly spread across many areas this evening from Southwestern Ontario and to the east of Lake Huron and Georgian Bay.

The snow is forecast to transition to freezing rain then to rain later this evening as temperatures rise above the freezing mark. One or two hours of freezing rain is likely north of Lake Erie and around the west end of Lake Ontario. More prolonged freezing rain is possible overnight in Eastern Ontario with potentially several hours worth before temperatures rise above zero very early Monday. This is not expected to be anything like the recent severe ice storm.

In the wake of the storm, bitterly cold west to northwest winds will develop on Monday. There is a risk of flash freeze conditions near the path of the low where temperatures have briefly risen above zero then fall sharply early Monday. This may include the Greater Toronto area. These winds will also produce widespread dangerous wind chills beginning Monday night as some of the coldest air in years produces record-shattering cold. Wind chill warnings will likely be issued later tonight.

Travel conditions are expected to deteriorate and become hazardous due to slippery conditions from snow and freezing rain, especially on untreated surfaces.

Environment Canada will continue to monitor this evolving situation and update warnings accordingly.

Please monitor the latest forecasts and warnings from Environment Canada at http://www.weatheroffice.gc.ca.

I went out and bought milk and bread. I can stay home tomorrow, check my e-mail, and communicate by computer. That sounds like a good plan. Stay safe if you have to drive and bundle up if you have to be outside for long.

Weather alert for Toronto, 4 January 2014

I like these detailed weather alerts.

City of Toronto
5:23 PM EST Saturday 04 January 2014
Special weather statement
for City of Toronto continued

Winter storm with heavy snow later Sunday and Sunday night, with mixed precipitation for some regions. Windy and sharply colder again Monday with some blowing snow and lake effect snow-squalls.

Old man winter is about to have another go at Southern Ontario as a winter storm developing over Oklahoma threatens the region.

A weak cold front from a separate weather system affecting Northern Ontario will slip into Southern Ontario tonight. This front will give a few centimetres of snow to many areas by Sunday morning, with 5 cm or more falling in locales east of Lake Huron to the south of Georgian Bay. This front will likely stall north of lakes Erie and Ontario on Sunday.

Meanwhile, a low pressure system developing over Oklahoma today will intensify and track northeastward along the line of the stalled front, crossing Southern Ontario Sunday night.

Some disorganized snow is expected on Sunday over some regions. As the deepening low approaches, the snow will become heavy over Southwestern Ontario Sunday afternoon and over the remaining regions Sunday evening. The snow will likely change to some rain near Eastern Lake Erie and Lake Ontario as well as parts of Eastern Ontario later Sunday evening. There is also a threat of some freezing rain in these areas. Any freezing rain that occurs will have virtually no impact on hydro for those areas impacted by the recent ice storm. But more significant freezing rain may impact travel to some degree over Eastern Ontario. Freezing rain warnings will likely be issued later tonight. The precipitation will taper off overnight Sunday or by early Monday in the east.

It appears that regions north of a line from roughly Leamington to London to Barrie to Pembroke will receive snowfall amounts of 15 to 20 cm. Amounts will likely be up to 5 cm south of that line with locally 10 cm in some areas.

In the wake of the storm, bitterly cold west to northwest winds will return on Monday, producing blowing and drifting snow in areas which receive the most snow from the storm. Furthermore, intense snow squalls are forecast to develop off Lake Huron and Georgian Bay Monday and persist into mid week.

Travel conditions are expected to deteriorate and become hazardous due to accumulating snow and poor visibility in heavy snow over Southern Ontario Sunday. If freezing rain falls, untreated surfaces may quickly become icy and slippery.

There is still some uncertainty as to the exact track of the storm centre and where the freezing rain and heaviest snow will fall. Environment Canada will continue to monitor this evolving situation and issue warnings accordingly.

It should be noted that widespread dangerous wind chills are likely especially from Monday night through Wednesday as some of the coldest air in years seems poised to settle across the region accompanied by brisk winds.

The public is advised to monitor future forecasts and warnings as warnings may be required or extended. Please monitor the latest forecasts and warnings from Environment Canada at http://www.weatheroffice.gc.ca.

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