Archive for the 'Weather & Sky' Category

Feb 29 2016

The Gift Of Time

Published by under Weather & Sky

Today we get the gift of time.  Leap Day, February 29, gives us 24 hours that are usually missing from our calendars.

You probably know we have to insert this day every four years because the earth revolves around the sun in approximately 365.25 days.  To make the calendar match the stars and seasons we add an extra day every fourth year with a complicated century exception.  The 4-year-old video above explains the details of this astronomical problem and how Julius Caesar and Pope Gregory XIII figure into it.

Last June 30 we received the gift of an extra second.  You probably missed it because it happened just before midnight.

Leap Second on June 30, 2015 (image from Wikimedia Commons)

Leap Second on June 30, 2015 (image from Wikimedia Commons)

Leap Years and Leap Seconds are unrelated but caused by a similar problem. Just as calendars must adjust for Earth’s rotation, so too must atomic clocks. The clocks are extremely accurate but Earth’s rotation is slowing down and not even at a consistent rate.  An extra second is added whenever the difference between mean solar time (UT1) and Coordinated Universal Time (UTC) reaches 0.9 seconds.  The need for this second is so unpredictable that it’s announced only six months in advance.  Computers hate this but there are workarounds.

In the past eight months we’ve gained 24 hours (on February 29, 2016) + 1 second (on June 30, 2015) + 1 hour (changed to Standard Time on November 1, 2015).  This nets us 25 hours + 1 second.

Do something fun with the gift of time.  Happy Leap Day!


p.s. We’ll lose an hour in two weeks on Sunday March 13 when we switch to Daylight Savings Time.  Yikes!

(Leap year video by Epipheo on YouTube. Leap second illustration from Wikimedia Commons; click on the image to see the original)

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Feb 08 2016

Winds On Water

Published by under Weather & Sky

Screenshot of animated Earth Wind Map from Click on the image to see the animation. (To help orient you, red dots were added to the map for Seattle, San Francisco and Los Angeles)

Screenshot of animated earth wind map from “earth: a global map of wind, weather and ocean conditions.”  Click on the image to see the animation. (I added 3 red dots to the map to help orient you: Seattle, San Francisco and Los Angeles)

Science Fun on Monday:

John English told me about this cool website that animates global weather, especially wind on water.  The website is called earth, “a visualization of global weather conditions forecast by supercomputers updated every three hours.”

Click on the screenshot above to see conditions in the eastern North Pacific. Before you do, here are some tips:

  • In the animation, slow winds are blue to green, intense winds are orange to red.
  • Everywhere on earth, the most exciting winds are those surrounding low pressure systems.  In the northern hemisphere, they circle counter-clockwise. (How to remember this? See below.)
  • Notice the blank zones where there’s no wind. The largest are often in the center of high pressure zones.  Some of these line up with the warm water “Blobs” that are killing seabirds by starvation.
  • If you watch for 60 seconds more winds on the continent will start to show up. They aren’t as intense.
  • Click and drag to change the location of the map.
  • Click on the word [earth] at bottom left to change the parameters.  Select a new Mode to see pollution (“chem”) or dust/smoke (“particulate”).

Follow this quick link to see the North Atlantic and Great Lakes map.  There’s usually less excitement here but look north toward Greenland and you’ll see why the North Atlantic is a dangerous place to cross in winter.

And for a really tangled mess of wind click here to see the air flow between South America and Antarctica!

Visit “earth” on Facebook for more screenshots and videos of amazing storms.  You don’t need a Facebook login; just click on the link.


BONUS: Here’s how to identify low and high pressure systems in the northern hemisphere based on the direction the winds are circling. Use the right-hand rule. Curl your fingers in the direction of the winds (B) and point your thumb. The air column (I) is moving in the direction of your thumb. Low pressure sucks the air column up; high pressure pushes it down. The orientation of this diagram would be a low pressure system in the northern hemisphere.

Right-hand rule, illustration linked from Wikipedia

(screenshot of the earth wind map from, right-hand rule illustration from Wikipedia)

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Jan 26 2016

Death By Warm Water

Common Murres, Peruvian Boobies (photos from Wikimedia Commons)

Common Murres, Peruvian Boobies (photos from Wikimedia Commons)

These two species — common murres and Peruvian boobies — have something in common. Both have starved in record numbers in the Pacific Ocean recently.

Common murres (Uria aalge) have a circumpolar range in the North Atlantic and North Pacific while Peruvian boobies (Sula variegata) are native to the west coast of South America yet both seabirds are affected by the same problem: warm seawater.

In the southern Pacific, the failed trade winds of El Niño have ceased the upwelling of cool undercurrents and raised the sea surface temperature near South America.  A similar lack of wind has caused three warm Blobs to persist in the Northern Pacific.  Sea surface temperatures in these regions are running 2oF to 7oF warmer.  That small rise doesn’t sound like much but it’s enough to scare off cold water fish and even generate toxic algae blooms.  There’s a drop in nutrients, a drop in fish life, and that means starvation for seabirds.

Three "blobs" of warm surface water in the Northern Pacific, 1 Sept 2014 (image from NOAA via Wikimedia Commons)

Three “blobs” of warm surface water in the Northern Pacific, 1 Sept 2014 (image from NOAA via Wikimedia Commons)

In June 2014 Peruvian boobies were the first wildlife indication of a strong El Niño when thousands of dead and starving boobies washed ashore on the coasts of Peru and Chile.  Their cold water fishery had failed.  Some were so desperate they flew way out of range to the Galápagos and Panama.

That winter, November 2014 to January 2015, Cassin’s auklets (Ptychoramphus aleuticus) became a warm water casualty on the U.S. West Coast.  In their case the original Blob was to blame.

And now 100,000 dead common murres have washed ashore on the coast of Alaska, victims of warm water in the Gulf of Alaska.

Where will it end?  The El Niño may weaken this spring but who knows when The Blobs will change?

For cold-water sea life, it’s death by warm water.


(photos from Wikimedia Commons. Click on these links to see the original photos of common murres and Peruvian boobies)

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Jan 24 2016

See Five Planets

Published by under Weather & Sky illustrates view of 5 visible planets 80 minutes before sunrise, Jan 20 - Feb 20, 2016 (image linked from illustrates the view of 5 visible planets 80 minutes before sunrise, Jan 20 – Feb 20, 2016 (image linked from

In case you didn’t hear this on the news last week … you’ll be interested to know that between January 20 and February 20 you can see all five visible planets 80 minutes before sunrise in an arch across the southern sky.  That’s Mercury, Venus, Saturn, Mars and Jupiter in order left to right.

The illustration above, linked from, shows where to look and when.  Click here or on the illustration to read more about this phenomenon.

Sunrise tomorrow, Monday, January 25, is at 7:35am in Pittsburgh, but before you set your alarm so you can be outdoors facing south by 6:15am you’ll want to know if it’s worth it. Pittsburgh’s skies are notoriously cloudy in the winter.  Will the sky be clear enough to see five planets?

To find out, check the handy chart for Pittsburgh here at

Here’s a sample of what you’ll find when you get there.  This is yesterday’s chart surrounded by an orange border to remind you that this is ONLY A SAMPLE! Click on the image to see the real thing.

Sample of chart for Pittsburgh, PA for SATURDAY JAN 23 2016 (Sample Only!)

Sample of chart for Pittsburgh, PA for SATURDAY JAN 23 2016 (Sample Only!)

On the chart, dark blue on the “Darkness” line is good.  The white to pale blue areas indicate cloud cover, moonlight or sunlight.

Check the chart and get up early between now and February 20.

If you don’t live in Pittsburgh, click here to find your location.

Good luck!


(illustration of five planets linked from plus a sample of the Pittsburgh Clear Dark Sky chart from

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Jan 23 2016

Confused About Names?

Published by under Weather & Sky

screenshot from winter storm newson The Weather Channel, 23 Jan 2016. Click on the image to read the story.

Screenshot from winter storm news on The Weather Channel, 23 Jan 2016. Click on the image to read the story.

If you’ve been paying close attention, you may have noticed that most media about this weekend’s weather calls it “the storm.”   It does not have a name. But if you tune into The Weather Channel, they call it Jonas.

In October 2012 The Weather Channel announced they would name winter storms to improve their communications about the storms.  This was not a popular move.

Within a month the National Weather Service announced they would not use the names. By February 2013 Accuweather, the New York Times, the Washington Post and others went on record that they wouldn’t use them either.

That’s why, three+ years later, only those who watch The Weather Channel call this storm by name.


(screenshot from The Weather Channel. Click on the image to see the news article at TWC)

p.s. On a personal note, I get my weather from the organization that provides the data (in the public domain & mostly free of charge!) that The Weather Channel uses to make their forecasts:  The National Weather Service

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Jan 14 2016

Find Water Using Satellites

Published by under Weather & Sky

Dowsing: George Casely finding water on his Devon farm,1942 (photo from Wikimedia Commons)

Coming this month is the lecture I’ve been waiting for.  On January 27 I’ll learn how NASA finds water using satellites instead of this old method of dowsing with a forked stick.

Since 2002 NASA’s paired GRACE satellites have been circling the globe measuring Earth’s gravitational pull.  What they’ve also discovered is a way to measure groundwater.

How do they do it?  Learn more here in my January 2014 blog post:  Dowsing From Outer Space.

Want to know more?

Come to the University of Pittsburgh Honors College lecture entitled:

Monitoring Groundwater Variability from Space

by Dr. Matthew Rodell, Chief, Hydrological Sciences Laboratory, NASA Goddard Spaceflight Center

When:  January 27, 2016,  4:00 PM

Where:  Alumni Hall, Connolly Ballroom, 4227 Fifth Ave

The lecture is free and open to the public but space is limited. Click here for more information and to reserve your seat.


(photo of George Casely dowsing on his farm from Wikimedia Commons. Click on the image to see the originals)

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Jan 13 2016

What El Niño means for the Galápagos

Published by under Weather & Sky

Map of annual sea surface temperature and distribution of penguins at the Galapagos (map from, adapted from original in Karnauskas, et al., 2015.)

Annual average sea surface temperature from 1982-2014 and penguin distribution (black lines). Nearly 70% of Galápagos penguins live where waters are coldest. Map from, adapted from the original map by Karnauskas, et al., 2015.

During our strangely warm and “yo-yo” winter it’s interesting to realize we’re not the only ones affected by this year’s El Niño.  The Galápagos Islands in the Pacific Ocean, 620 miles west of South America, are having a much wilder time of it.

Though located on the equator the Galápagos have a cooler and drier climate than you’d expect because of an important ocean current and the prevailing wind.

The Equatorial Undercurrent (also known as the Cromwell Current) is a wide river of cool water moving west to east from Indonesia to South America, 300 feet below the surface.  Because the Trade Winds blow east to west they push surface water away from the archipelago’s western shore.  When the Equatorial Undercurrent reaches the islands it wells up to fill the surface void and effectively lowers sea surface temperatures west of the islands (see map above).

Cold water is good.  It supports more phytoplankton (tiny chlorophyll-producing organisms) than warm water and that supports the entire food chain all the way up to seabirds, mammals and unusual reptiles:  blue-footed and red-footed boobies, Galápagos penguins, Galápagos fur seals and marine iguanas to name a few.

As proof that cold water is good, the map above shows that Galápagos penguins live where the water’s cold. That’s where the fish are.

Galápagos Penguin, Galápagos Islands, Ecuador (photo from Wikimedia Commons)

Galápagos Penguin, Galápagos Islands, Ecuador (photo from Wikimedia Commons)

El Niño changes everything.  The trade winds subside or change direction, the undercurrent no longer wells up and sea surface temperatures rise. The warmth causes a drop in nutrients and the entire food chain suffers.  Fish populations drop.  Seabirds, mammals and, yes, penguins starve.

This year’s El Niño began forming in mid 2014 and was even then so intense that seabirds were starving off the coast of Chile in June 2014.  (see photo on the ABA Blog)

However, something good does comes of El Niño.  In the Galápagos there’s a population boom among land-based birds.  There, the rainy season is the breeding season and El Niño brings rain, sometimes quite a lot of it.  During the strong El Niño of 1982-83, cactus and Fortis finches (Darwin’s finches) bred like crazy, increasing their populations by 400%.

While immensely bad for some species, it’s very good for others.

That’s what El Niño means for the Galápagos.


(map from blog, El Niño and the Galápagos. Photo of Galápagos penguin from Wikimedia Commons.  Click on the images to see the originals.)

For more information see these sources:
* The Beak Of The Finch by Jonathan Weiner, especially pages 100-104.
* Blog:  El Niño and the Galápagos by Kris Karnauskas.
* Climate of the Galápagos Islands by Chris Ader, University of Maryland

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Jan 09 2016


Flowering cherry tree in snow, 4 Jan 2016 at Carnegie Museum in Pittsburgh (photo by Kate St. John)

Flowering cherry tree in snow, 4 January 2016 in Pittsburgh (photo by Kate St. John)

After a month of warm weather, these cherry trees were fooled into blooming in early January at Carnegie Museum.

Then last Monday the temperature dropped into the single digits and hit everything that couldn’t get out of its way.  Nothing could protect those delicate pink flowers.

Unlike plants, birds can get out of the way and some of them decided to leave this week.  In my neighborhood, there were many American robins in December but most of them have left since the cold snap.  Did your robins leave, too?

Meanwhile, don’t be fooled by today’s warmth.  Here’s a graph of Pittsburgh’s actual and predicted morning low temperatures for the first two weeks of January.

Graph of morning low temperatures in Pittsburgh, PA, actual+forecast for January 1-14, 2016 as of 1/9/2016 (graph uses NWS data)

Actual+forecast morning low temperatures in Pittsburgh, PA, January 1-14, 2016 (graph uses National Weather Service data as of 1/9/16)

It’s a yo-yo.


(photos by Kate St. John)

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Jan 05 2016

Ice Is Way Cool

Published by under Weather & Sky

This morning it’s 8o F and we certainly have ice in Pittsburgh!

Did you ever think about how unusual and important it is that ice floats?

Watch the video above to learn how it happens.

Ice is way cool!


(video from Naked Science Scrapbook on YouTube)

p.s. I’ve been waiting since November to write about ice. December was mostly ice-free and often quite warm. What a winter!

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Jan 02 2016

December Rose

Published by under Plants,Weather & Sky

A rose in Pittsburgh, 30 Dec 2015 (photo by Kate St. John)

Rose blooming in Pittsburgh, 30 Dec 2015 (photo by Kate St. John)

This week I found several roses in bloom in my neighborhood.

Roses blooming at the end of December?  In Pittsburgh?

Last month there were only two nights below freezing at the airport (Dec 18-20, 29 to 30oF), but it probably didn’t drop below freezing in my city neighborhood.  This coming Monday night, January 4, the low is predicted to be 12oF.

That’s what a crazy winter it’s been!


(photo by Kate St. John)

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