Tuesday, September 30, 2014

Fall Colors in the Great Lakes--As Seen from Space

Two days in a row I will post pictures from the website http://earthobservatory.nasa.gov/ since today NASA is featuring the fall colors of the Great Lakes region.  They posted two photos: 

The text included in NASA's post is:

"A few days after autumn showed up on the calendar in the Northern Hemisphere, it showed up on the landscape of North America. ...NASA... captured these views of fall colors around the Great Lakes (September 26) and New England (September 27, 2014). The brown and orange shades are most pronounced in the Upper Peninsula of Michigan, northern Wisconsin, upstate New York, New Hampshire, Vermont, Maine, and southern Quebec and Ontario. You can also see faint traces of phytoplankton blooms in the lakes and offshore in the North Atlantic.

The changing of leaf color in temperate forests involves several causes and reactions, but the dominant factors are sunlight and heat. Since temperatures tend to drop sooner and sunlight fades faster at higher latitudes, the progression of fall color changes tends to move from north to south across North America from mid-September through mid-November.

In late summer and autumn, tree and plant leaves produce less chlorophyll, the green pigment that harvests sunlight for plants to convert water and carbon dioxide into sugars. The subsidence of chlorophyll allows other chemical compounds in the leaves—particularly carotenoids and flavonoids—to emerge from the green shadow of summer. These compounds do not decay as fast as chlorophyll, so they shine through in yellows, oranges, and reds as the green fades. Another set of chemicals, anthocyanins, are associated with the storage of sugars and give the leaves of some species deep purple and red hues.

As explained by the U.S. Forest Service, certain species of trees produce certain colors. Oaks generally turn red, brown, or russet; hickories become golden bronze; aspen and yellow-poplar turn golden. Maples differ by species. Red maple turns brilliant scarlet; sugar maple, orange-red; and black maple, yellow. Leaves of some trees, such as elms, simply become brown.

Weather affects the range and intensity of colors. If the weather stays above freezing, it is easier for anthocyanins to form. Dry weather, which increases the sugar concentration in sap, also increases the amount of anthocyanin. So the brightest autumn colors occur when dry, sunny days are followed by cool, dry nights.

According to a paper published last month by researchers from Princeton University, climate change could someday delay the onset of fall color changes in some species, but also extend it later into the year. Warmer temperatures could lengthen the growing season for some plants, though more so at middle latitudes than high latitudes."

Just for fun, I am including two more photos below from the same webpage.  It shows the same area in the Appalachian Mountains -- one taken during the summer and one during the fall.

NASA image courtesy Jeff Schmaltz, LANCE MODIS Rapid Response Team at NASA GSFC. Caption by Mike Carlowicz.

Monday, September 29, 2014

NASA Photos Showing the Destruction of the Aral Sea

As many of you know, every once in a while I check in with NASA's Earth Observatory website at http://earthobservatory.nasa.gov/ .  Today the website is featuring the dramatic difference in the Aral Sea, located in western Russia. 

Formerly the Aral sea was one of the four largest lakes in the world with an area of 68,000 square km (26,300 sq mi) and 1,534 islands.  Now the lake is almost gone.  The Aral Sea has been steadily shrinking since the 1960s after the rivers that fed it were diverted by Soviet irrigation projects. By 2007, it had declined to 10% of its original size, splitting into four lakes. By 2009, the southeastern lake had disappeared and the southwestern lake had retreated to a thin strip at the extreme west of the former southern sea; in subsequent years, occasional water flows have led to the southeastern lake sometimes being replenished to a small degree.The maximum depth of the North Aral Sea is 42 m (138 ft) (as of 2008).

The shrinking of the Aral Sea has been called "one of the planet's worst environmental disasters".The region's once-prosperous fishing industry has been essentially destroyed, bringing unemployment and economic hardship. The Aral Sea region is also heavily polluted, with consequent serious public health problems. The retreat of the sea has reportedly also caused local climate change, with summers becoming hotter and drier, and winters colder and longer.  The series of NASA photos from 2000 to 2014 is below.

In an ongoing effort in Kazakhstan to save and replenish the North Aral Sea, a dam project was completed in 2005; in 2008, the water level in this lake had risen by 12 m (39 ft) compared to 2003. Salinity has dropped, and fish are again found in sufficient numbers for some fishing to be viable. The Aral Sea watershed encompasses Uzbekistan and parts of Tajikistan, Turkmenistan, Kyrgyzstan and Kazakhstan.

Hopefully the powers that manage the Great Lakes watershed are taking notice.

Zafiroblue05 : http://en.wikipedia.org/wiki/Aral_Sea#mediaviewer/File:Aral_Sea_1989-2008.jpg

Saturday, September 27, 2014

4th of July Agate Close Ups

Several weeks ago I posted a few photos of the unusual Lake Superior agate that I purchased earlier this summer from Mark Bowen.  As I already reported, this is the first time in 16 years that I negotiated to buy a single rock off of someone who came into the museum.  Mark had purchased this inland agate from EBay.  When he received it in the mail, it was very rough with a thick husk.

Mark spent an hour on his standard grinding wheel and removed the husk.

I used my Nikon camera with close up lenses to get a few more photos.

With my USB microscope camera I took a few photos.  Since Mark used just a grinding wheel and I don't want to complete the face polish since we think any more lapidary work could remove some of the detail, you can see some of the grinding streaks.

Friday, September 26, 2014

Log Slide to Au Sable Point Lighthouse -- Post 3

Today I will post the last of the photos that I took during the hike I took on Tuesday with Mark and Clare Comstock.

I prefer loop trails, but the Log Slide trail certainly gives you different views on the hike back east.

Mark spotted the eagle.  I had a hard time finding it with the zoom, so Mark was able to use my camera and capture the photo.

Sister and brother.....

After dinner, we headed down to the "front porch" to catch yet another beautiful Lake Superior sunset.

Thursday, September 25, 2014

Log Slide to Au Sable Point Lighthouse Hike -- Post 2

Today I will post the second of three sets of photos taken during a hike on Tuesday of this week with friends, Mark and Clare.

It is hard to tell what is going on in the following picture.  It is a land bridge with an opening down to the beach.  And no, we did not test the strength of the land bridge.

It was a beautiful day to walk along the shoreline.

Looking back toward the Grand Sable Banks.

After a two mile hike we broke out of the woods into the lighthouse complex.

I put my camera on top of the back pack and took a ten second delay photo.  Mark, Clare, and me...


Time to head back...