Archive for the 'Weather & Sky' Category

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 climate.gov, 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 climate.gov, 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 Climate.gov 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.
* Climate.gov 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

Yo-yo

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!

2 responses so far

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)

8 responses so far

Dec 30 2015

Drunk On Climate Change

Ornamental fruit in December after a couple of frosts (photo by Kate St.John)

Ornamental fruit in December, after a couple of frosts (photo by Kate St.John)

Freeze. Thaw. Freeze. Thaw.  In this non-winter of 2015 we’ve had days and weeks of warmth punctuated by occasional frosts.  Eventually the freeze-thaw cycle produces fermented fruit and that leads to drunken birds.

Fruit ferments outdoors when freezing temperatures break down the hard starches into sugars and then a thaw allows yeast to get into the softened fruit and begin the fermentation process.

The sweet, soft fruit is particularly tempting to birds.  After a good frost the ornamental trees in my neighborhood, like the one above, are swamped with hungry starlings and robins.  When they swallow a fermented berry it has a fizzy zing, but so what?  It tastes good.

But some birds don’t know when to stop.  They eat so much fermented fruit that they walk with a wobble and can’t fly straight.  When they’re falling-down drunk, they end up in “detox” at a wildlife center until they sleep it off.  Bohemian waxwings are famous for this.

Back in 2014 National Geographic reported on an incident in Whitehorse, Yukon when a bumper crop of fermented rowan (mountain ash) berries were the waxwings’ undoing.  The birds were in such bad shape that they ended up in Meghan Larivee’s “drunk tank” at Environment Yukon.

It turns out climate change is increasing the likelihood of these episodes up north.  National Geographic explains:

Larivee’s recent waxwing patients were admitted to her Yukon animal unit following several frosts and thaws due to warmer temperatures. … While fermentation is most pronounced in winter, “we also likely have longer autumns, which gives more time for berries to ferment, but still have early frost that allow sugars to be produced in berries early in the fall,” she said.

The waxwings were drunk on climate change.

 

Read more here in National Geographic.

(photo by Kate St. John)

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Dec 24 2015

Dreaming of a White Christmas

Published by under Weather & Sky

Snowy winter scene in western Pennsylvania (photo by Steve Gosser)

Snowy winter scene in western Pennsylvania (photo by Steve Gosser)

This year’s El Niño has made it too warm for snow on Christmas.  Way too warm!

Today’s forecast high of 65o F is almost 30 degrees above normal.

In Pittsburgh it’s going to feel like Christmas in Florida without the palm trees. Florida will be hotter than normal, too.

 

High Temperatures Forecast for contiguous U.S., 24 Dec 2015 (map from National Weather Service)

Daytime High Forecast, 24 Dec 2015 (map from National Weather Service)

No snow, no skiing east of the Mississippi.

We’ll just have to dream …

 

(photo by Steve Gosser)

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Dec 20 2015

Solstice Soon

Published by under Weather & Sky

Winter solstice sunset at Kolkata (Calcutta), 22 Dec 2011 (photo from Wikimedia Commons)

Winter Solstice sunset at Kolkata, India, 22 Dec 2011 (photo from Wikimedia Commons)

Now matter where you are on Tuesday December 22 at 4:48 am UTC — in Calcutta, India (above) or the frozen Yukon — you’ll experience the northern solstice.   (NOTE that December 22, 4:48am is Universal Time!  In Pittsburgh the solstice is at 11:48pm on Monday December 21.)

Here at latitude 40o North we think the solstice is a northern daylight event but it’s actually an astronomical event that happens everywhere on Earth at the same moment.  At the North Pole there’s nothing to see; it’s been dark for a long time.  In Australia they’re having their longest summer day.

In Pittsburgh we reached our shortest number of (rounded) minutes on December 17 — 9 hours and 17 minutes — and we’ll stay there, gaining only seconds per day, until December 26.  Then on the last day of the year we’ll begin to gain a minute a day.  At last!

Here’s good news for people with Seasonal Affective Disorder (SAD):  We’re going to turn the corner soon.

 

(photo by Biswarup Ganguly via Wikimedia Commons. Click on the image to see the original)

 

3 responses so far

Nov 21 2015

Violets In November

Published by under Plants,Weather & Sky

Violets blooming on November 13 in Pittsburgh (photo by Fran Bungert)

Violets blooming on 13 November 2015 in Pittsburgh (photo by Fran Bungert)

Just over a week ago Fran Bungert was walking in South Park with her husband and dogs when she came upon some violets in bloom and sent me this picture from her cellphone.

November is a very odd time for violets (Viola sororia sororia).  They normally bloom from April to June.

Are they confused by our warm El Niño autumn?  Or have some violets always bloomed in November and I’ve just not paid attention?

What do you think?

 

(photo by Fran Bungert)

6 responses so far

Aug 12 2015

Localized Drought

Published by under Weather & Sky

Woodland boneset leaves wilting in dry weather, Pittsburgh, 9 August 2015 (photo by Kate St. John)

Leaves wilting in my dry backyard, 9 August 2015 (photo by Kate St. John)

Ever since May’s dry weather, Marianne Atkinson and I have kept up a lively email conversation about drought and rain in our respective hometowns, Dubois and Pittsburgh.

Dubois has been short-changed on rainfall this year despite June’s excessive wet weather.  Most months have been so dry that June’s 3.36″ above normal could not overcome the drought.

Even their “good” rainfall statistics are misleading because most of it falls in a single heavy downpour event.  As of today, Dubois received 1.3 inches of rain in August but 98% of it fell in one 24 hour period — August 10-11.

We shouldn’t be surprised.  Climatologists predict that as the climate heats up western Pennsylvania’s weather will change from gentle rains to frequent heavy downpours.

Meanwhile Marianne watches the weather radar closely.  When rain is predicted will her garden get any of it?  No. As the storm clouds approach they usually part north and south, missing Dubois completely.  She sent me this screenshot of a recent “rainy” day from Accuweather.

Rain misses Dubois (radar screenshot from Marianne Atkinson)

Rain misses Dubois, August 2015 (Accuweather screenshot captured by Marianne Atkinson)

I’ve seen this phenomenon, too.  On Monday night Pittsburgh got a trace while Youngstown and West Virginia were slammed.

It's raining everwhere but here (Radar image from National Weather Service, Pittsburgh)

It’s raining everwhere but here (Radar image from National Weather Service, Pittsburgh)

Is your town suffering from localized drought?  Have you noticed this parting-of-the-clouds phenomenon?

It reminds me of Arizona’s monsoon.

 

(photo by Kate St. John)

5 responses so far

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