Tuesday, May 8, 2012

Do I Need An Umbrella...Or Not?!





We tend to blame the meteorologist when local forecasts fail to meet our expectations, but let's not kill the messenger.   Meteorologists receive their data from sophisticated equipment that they then interpret on a local scale and what that means in terms of weather for given communities.  Several steps prior, at the sending end of this transmission are satellites officiated by governing factions such as NOAA (National Oceanic and Atmospheric Administration).

Remote sensing has come far since the time of earths first aerial photographs in the 30's.  Satellite technology has moved from early prototypes in the 1950's to GOES (Geostationary Operational Environmental Satellites) synchronous orbiting satellites.   Numbers of weather monitoring instruments currently help the administration track and advance warn of threatening conditions such as hurricanes and tornadoes.  The progress of such technologies is reported to be on the decline due to limited funding and budget cuts according to recent analysis completed by the National Research council May 2, 2012.

The number of monitoring instruments will go from 110 last year to less than 30 by the end of the decade according to the report.   Earth observation missions by NASA and NOAA are expected to decline from 23 to about 6 by 2020 as a result of these cuts.  The result?  Less data for our reporting agencies and professionals to make accurate forecasts and negative impacts on advance warning advisories for hazardous conditions.  So dress in layers, listen for high winds and hone your wet finger wind direction test abilities, because it seems our verbal weather writers have just had their pencils removed.

References

King, Ledyard. "Report warns of weather satellites' 'rapid decline'." USA Today 2 May 2012, online ed. Web. 8 May 2012. <http://www.usatoday.com/weather/news/story/2012-05-02/weather-satellites-forecast-storms/54708804/1>.


Arbogast, Alan F. Discovering Physical Geography. second ed. Hoboken: John Wiley and Sons, 2011. 355-59. Web. 22 Apr. 2012.


Report Warns of Rapid Decline in U.S. Earth Observation Capabilities. Environmental Protection, 7 2012. Web. 8 May 2012. <http://eponline.com/articles/2012/05/07/report-warns-of-rapid-decline-in-u.s.-earth-observation-capabilities.aspx>.


Monday, May 7, 2012

Not In MY Beach Yard


Many people enjoy the dream of a simple life.. with a little house on the beach, toes in white sand and a view of the horizon.  Some of those people succeed and are able to buy that beachfront property.  But there lies a friendly beast called erosion, who doesn't care how many figures you make a year, or how pretty that house is in the backshore.  Longshore currents will propel waves obliquely at that white luxurious sand, and backwash it into the sea. Yet here's where money does matter.   If you have enough of it you can build a protective structure called a 'groin' that will help you sustain that piece of beach right in front of your house.

It's a popular type of beach nourishment that can be seen up and down the Jersey shore, around Lake Michigan and many other popular shorelines for homeowners.
Here is where it becomes a problem.  If homeowner A erects such a sand stabilizer, it will create a zone of erosion for landowner B.  It makes the longshore current regenerate further down coast (Fig. 3.1).   But groins can be an integral part of preserving breeding areas of endangered birds, or keeping inland areas from flooding.  Arguments on who then can erect these structures are making their way off the shore and into courts. 

Fig. 3.1 – beach groin erosion patterns

Image source: USGS site: 

The BlueRibbon Committee on Shoreline Management propose to ban the use of these structures in South Carolina.  In this state, over 166 groins extend from the shore, and that's just the region of shoreline  south of Myrtle Beach!  Areas of beach below these groins erode faster than normal due to the depletion of sand from shifted currents, making the dream of toes in white sand a bit more of a nightmare for some of the shore's anthropogenic dwellers.


References


WCBD News 2. Associated Press, 2 May 2012. Web. 2 May 2012. <http://www2.counton2.com/news/2012/may/02/sc-panel-recommends-no-more-beach-groins-ar-3716471/>.
Barton, Tom. Shoreline committee urges ban of groins. Chicago News Tribune, 3 May 2012. Web. 5 May 2012. <http://www.chicagotribune.com/news/sns-mct-shoreline-committee-urges-ban-of-groins-20120503,0,6202891.story>.
Herring, Brandon. SC could abandon certain erosion-prevention efforts. WMBF News, 2 May 2012. Web. 8 May 2012. <http://www.wmbfnews.com/story/18067377/sc-could-abandon-certain-erosion-prevention-effort>.

New Thoughts On Subduction


Geologists and many other geographically centered scientists have argued for decades over how the process of plate tectonics had initially evolved.  Recently,  Jeroen van Hunen, a geophysicist at Durham University in England worked with Jean-François Moyen, of Jean Monnet University in Saint-Etienne, France to give us their theories.  A model was developed showing how one plate of earth's thin crust subducts below another.
The theory thus far has supported a continuous process where plates converge at boundary points, and are famously based on movement fuelled by temperature and/or substrate mass and density (i.e dense continental crust v. the lighter basaltic rock of oceanic crust).  Some theories in the past have been maintained by evidence of rocks surfaced from mantle regions of the lithosphere and have supported more of a continuous motion of plates at boundaries resulting in subduction (Fig 2.1).

Fig. 2.1 - subduction zone of two plates

photo credit:. Web. 2 May 2012. <volcanoes.usgs.gov>
Moyen and Hunen found rocks striated with pristine rocks layered with altered rock in Zimbabwe and Southern Australia that account for more of a 'start and stop' method of initially forming our modern day plate tectonics.   The discussion follows one of geothermal interest and spotlights convection loops.  The two scientists did their study showing their audiences how changes as few as 200 degrees higher, would cause crust to break off and interrupt the continuous flow theory.  It would take time for the layer to cool enough to begin re-subduction which if anything but a good argument, supports how the ancient rock striations in Zimbabwe have been aligned as they are.

References

Witze, Alexandra. "Stop-and-go plate tectonics." Science News 9 Apr. 2012. Web. 2 May 2012. <http://www.sciencenews.org/view/generic/id/339797/title/Stop-and-go_plate_tectonics>.
Arbogast, Alan F. Discovering Physical Geography. second ed. Hoboken: John Wiley and Sons, 2011. 355-59. Web. 22 Apr. 2012.
Glasscoe, Maggi. History of Plate Tectonics. N.p., n.d. Web. 17 Mar. 2012. <http://scign.jpl.nasa.gov/learn/plate2.htm>.

The Cost of Change


It's rare to be anywhere on the planet these days without hearing about climate change and how it impacts life on earth.  No stranger to this phenomenon are the people living near the Bay of Bengal surrounded by pristine snorkeling opportunities such as those found outside the Andaman Islands (Fig 1.1).  Since the 2004 tsunami hit South Asia, many governments have invested in tourism to boost rebuilding costs caused by the tsunami devastation. 

Fig. 1.1 - Andaman Islands 



Climates in that area experience little change in temperature throughout the year ranging 2 degrees F over 12 months.  The Koppen classification system marks this 'Am' Tropical Monsoon as such due to the dry season the area experiences.   This is the variation that distinguishes places such as the Andaman islands from tropic rainforest regions.  With dependence on mT air behind onshore flow, the wind circulates in such a way that air shifts once a year bringing cooler temperatures and heavy rainfall during summer months (Fig 1.2). 

Fig. 1.2 -  climograph for Mangalore, India



It is theorized that warming bay area waters are behind the delay in this wind circulation shift allowing shallow waters near the Andaman Islands to stay warmer for longer periods of time resulting in devastating impacts to symbiotic algae that keep corals thriving.  Evidence of this can visually be measured by levels of 'coral bleaching' witnessed in the area following the delay of monsoon rains this year.  While it may increase the dollars and cents brought to economic regions surrounding the area, the change brought by climate won't lead tourists to stunning reefs in the Andamans this year.

References


N.p., n.d. Web. 17 Mar. 2012. < http://www.ncdc.noaa.gov/paleo/outreach/coral/sor/sor_indian.html >.
Gies, Erica. "Holding On to What Was in the Andamans." The New York Times 12 Feb. 2012: TR+. Web. 22 Apr. 2012.
Arbogast, Alan F. Discovering Physical Geography. second ed. Hoboken: John Wiley and Sons, 2011. 214-18. Web. 22 Apr. 2012.