12 December 2013

Amber is a rock that started as tree resin.  When it was resin it collected pollen, flecks of dirt, plants, small creatures, and other debris as it flowed from the tree. The amber above contains a spider, air bubbles, dirt and an ant, all preserved when the resin hardened.

Scientists are fascinated by amber because everything inside it is as old as the rock.  In 2013 an international team led by Ralf Tappert of the University of Innsbruck analyzed carbon-12 and carbon-13 in present-day tree resin and amber dating all the way back to the Triassic period.  They chose amber for their chemical analysis because, as Tappert explains, “Compared to other organic matter, amber has the advantage that it remains chemically and isotopically almost unchanged over long periods of geological time.”

From 538 samples they calculated the concentration of oxygen in the atmosphere for 220 million years of the Earth’s history.  Surprisingly, they learned that the concentration in the early Cretaceous period was only 10-15% compared to 21% oxygen today.  The dinosaurs had less oxygen to breathe than we do!

This finding tossed out at least one theory about the dinosaurs, namely that their size was possible because they had so much more oxygen to breathe.  Oops!  They had less.

Click here to read more about the study at ABC Science (Australia).

Ancient air tells the tale.

(photo from Wikimedia Commons. Click on the image to see the original)

p.s. The concentration of oxygen in the Cretaceous was similar to the effective oxygen percentage at the top of Pikes Peak or Mt Everest Base Camp.

Earlier this year NOAA Coastal Services Center and NOAA’s climate.gov debuted an interactive mapping tool showing the effects of sea level rise on the US coast.  I learned about the Sea Level Rise Viewer in the video above.

Though we’re in no danger in Pittsburgh my family lives within 10 miles of the coasts of Virginia, Maryland, Florida, Massachusetts and New York so I was particularly interested in those places.  Some places near them, such as Norfolk, Virginia, are already experiencing nuisance flooding.

Using the tool I zoomed in on a favorite birding location: Merritt Island National Wildlife Refuge off Titusville, Florida.

One foot of sea level rise will put some of Merritt Island underwater and surround the access road from Titusville.  Two feet will make it impossible to cross from Titusville and will bury Blackpoint Wildlife Drive. Here’s a screenshot of the two-foot rise.

Try the tool yourself.

1. Watch the video above to see how the Viewer works.
2. Click on this link for the Sea Level Rise Viewer.
3. Enter an address in the search box or double-click on the map to zoom in on your favorite place.
   
4. Now use the controls on the left panel to see the effect.  Move the blue sliding bar up to make the water rise.
   

It’s amazing what a little rise in sea level can do.  Some day Merritt Island will disappear.

(video and screenshots from NOAA Coastal Services Center)

Riffing on the number 2,000… yesterday I wrote about a hummingbird drawing 2,000 years old.  Today…  Ta dah!  This is my 2,000th blog post!

Almost six years ago I began blogging every other day.  By now I write daily posts and more when there’s breaking peregrine news.  My husband notes that this sustained effort is roughly equivalent in length to War and Peace.

That’s a heck of a lot of writing, so for today I’m going to take a break and encourage you to do two things using the panel on the left:

1.  Try the search box.  Find something interesting in my other 1,999 entries.  Search for anything — a noun, a verb, an adjective.  Below you can see that I searched for the word “intriguing.”  Scroll down to read older posts you may have missed.

2.  Donate to the blog.  My blog is hosted at WQED Pittsburgh, where I work as Director of Information Technology for both TV and radio.  Like all public broadcasting stations we rely on donations to keep us going.  If you like this blog, make a donation of any size to show your support.  Click on the hummingbird graphic.

Thanks!

p.s. The screenshot below shows you what to do.

(photo of fireworks in the public domain from pdphoto.org via Wikimedia Commons. Click on the image to see the original)

Here’s a 2000-year-old drawing of a very cool bird.  Can you tell which one it is?  (For a better view, click on the caption to see the larger original.)

While researching hummingbirds I learned about this geoglyph, one of the many Nazca lines found on the dry landscape of southwestern Peru near the towns of Nazca and Palpa.  From the air the land looks like a giant sketchpad with hundreds of lines, geometric figures, humans and animals.  There are even erasures and newer drawings superimposed on top of old ones.

The Nazca people created these lines when their culture thrived here between 500 BC and 500 AD.  The figures were community projects created by removing the top layer of dark reddish pebbles to reveal the light-colored lime soil beneath.  This desert is one of the driest places on earth and so stable — no wind, rain or vegetation — that the lines have endured to this day. They were protected as a UNESCO World Heritage Site in 1994.

The geoglyphs are as large as 660 feet across, some drawn on hillsides like murals, others in the valley.  The hummingbird is 305 feet long and is a single line that can be walked without crossing itself.  Archaeologists believe these walks were ceremonial, possibly done as a group or community.

I’m impressed that people can create a shape on this scale.  The artist has to spatially translate a small drawing into landscape size.  I can do this for easy things such as “walk in a circle in the living room” but nothing like this!   (In Pittsburgh we’ve done this as flash mobs that spell Google or make the shape of a Pitt Panther.)

Line-making in the Peruvian desert ended after 800 years because of local climate change.  The Nazcas’ only water came from horizontal wells and intermittent rivers fed by rain on the western slopes of the Andes.  When that rain ceased to fall, the wells and rivers went dry and that was that.

See more of the drawings in this six minute slideshow.

(photo from Wikimedia Commons.  Click on the caption to see the original)