Wednesday, March 20, 2013

Spring 2013: DELAYED



It’s spring!

The vernal equinox on March 20, 2013.  It is that time of year again (it happens twice) when the relative angle of Earth is perpendicular to the Sun, causing equal incoming solar energy to the Northern and Southern hemispheres - as well as equal day and nighttime. At 7:02 ET on March 20, 2013, Earth was at its equinox. At 7:45 ET, the GOES-13 satellite captured this full disk image of Earth.  Click on the image for a larger view.  Image Credit: NOAA.

Both meteorological and astronomical springs have arrived.  The vernal equinox marks the beginning of spring in the Northern Hemisphere.  This is when the vertical rays of the sun are directly over the earth’s equator and crosses the equator on its northward journey.

Funny, it doesn’t feel like spring.  Let me check the forecast:

The 5-day forecast for March 20, 2013 for Columbia, SC.  Image Credit: WLTX-TV.

Remember those groundhog forecasts from six weeks ago.  A couple of them got it right, but most got is wrong.  Not only did spring not come early, it does not appear to be in sight.

Friday, March 15, 2013

Energy And Climate



The 2013 annual meeting of the American Meteorological Society took place this past January in Austin, Texas.  One of the topics was that of energy and climate.  Billionaire T. Boone Pickens spoke on Sunday evening before the annual meeting began.  It was an enjoyable evening and interesting to hear was he had to say.

T. Boone Pickens
First, he holds a degree in geology from Oklahoma State University.  Pickens said “I’m one of the few (petroleum) geologists that agree that global warming is happening.”  He agrees that we need to do something to mitigate the effects of the warming.  It is smarter to do something to avoid the problem rather than waiting until it happens to do anything.

However, he went on to say that hydrocarbons (fossil fuels) would be with us for the next 50 years.  Pickens said that wind and solar represent just 2% of the energy generation and he didn’t think that it would become substantial until it became economically more competitive with fossil fuels.  That means a price of about $6 for natural gas (it is just under $4 today).

Pickens is against the idea of a carbon tax or cap & trade.  However, he did not say whether he agreed with the idea of ending fossil fuel subsidies.  Tom Friedman of the New York Times has an interesting article on attacking carbon emissions and the fiscal debt.

Monday, March 11, 2013

Comet PANSTARRS



Comets bright enough to be seen without the aid of a telescope or binoculars are a rarity.  This year may produce two such events.  The first is now visible in the western sky after sunset, weather permitting.  Comet PANSTARRS is actually Comet 2011 L4.  Discovered in June 2011, comet 2011 L4 (PANSTARRS) bears the name of the telescopic survey that discovered it; "Panoramic Survey Telescope and Rapid Response System" which sits atop the Haleakala volcano in Hawaii.

The comet moved into the view of the Northern Hemisphere last week, but the best views should be over the next two weeks.  You can follow continuing updates on the progress of the comet at Sky and Telescope.  Viewing the comet may still be a challenge.

Comet C/2011 L4 PANSTARRS as seen from Mount Dale, Western Australia. The lights on the distant horizon are from the city of Armadale, which is southeast of Perth. Click on the image for a larger view. Image credit: Astronomy Education Services/Gingin Observatory.

Monday, March 4, 2013

Southeast Drought Improves



What a difference a month can make.  The drought situation was becoming serious at the end of January as I wrote here.  Yet, February saw an abundance of rainfall creating a substantial surplus for the month.

Monthly rainfall for February in Columbia, SC.  Image Credit: WLTX-TV.

Monthly observed rainfall for February, 2013, covering South Carolina as well as parts of Georgia and North Carolina.  Click on the image for a larger view.  Image Credit: NOAA/AHPS.

In South Carolina the heaviest rainfall occurred over the southern half of the state.  Some parts of the low country saw over ten inches of rain for the month.  The least rainfall occurred over the north central section where rainfall was in the three to four inch range.  However, this area saw more rain in January so that the two-month total is substantial.

A series of storm systems moved through the Southeast pumping moisture from the Gulf of Mexico northward.  The heaviest rainfall occurred across southern Alabama, southern Georgia, and parts of northern Florida.  The drought was center in central Georgia which had experienced extreme to exceptional drought conditions for over a year and a half.

Friday, March 1, 2013

A Change In The March 2013 Outlook



The Climate Prediction Center (CPC) issues outlooks for the next month in the middle of the current month.  They will often issue an updated outlook near the last day of the current month.  Usually these projections do not vary much, but this month saw a substantial revision.

Computer models designed to forecast daily weather are run out to 15 days, four times each day.  Most are familiar with the 7-day forecast.  The CPC also issues 8-14 day outlooks for the second week of the forecast in additions to the monthly and seasonal outlooks that they make each month.

Beginning with the 8-14 day temperature outlook on February 21 and the one issued on February 28, it seems that the first half of March would be colder than normal for South Carolina as seen in the outlooks below.

The 8-14 day temperature outlooks.  The first one made February 21 and the second one (right) made February 28.  Click on the image for a larger view.  Image Credit: NOAA/CPC.

The reason for this projection is that the Arctic Oscillation (AO) has been in a negative phase with the forecast for it to become strongly negative next week.  This usually produces a cold outbreak for parts of the U.S.  Last year the AO was strongly positive and the U.S. saw the warmest March on record.