Thursday, January 30, 2014
Tuesday, January 28, 2014
Monday, January 27, 2014
UNITED STATES The Pentagon took steps to give individual troops greater latitude to wear religious clothing with their uniforms, but some Sikh groups say the new policy falls short. (Reuters) Use our resources to better understand Sikh articles of faith, including turbans and uncut hair. Discussion Ideas Read through our "media spotlight" on Sikh dastaars, […]
Wednesday, January 22, 2014
Thirteen years ago, a satellite acquired this beautiful image (above) of light and sand playing off a portion of the ocean floor in the Bahamas. The caption that accompanied the image didn't include many details, only noting that the image was acquired by the Enhanced Thematic Mapper Plus (ETM+) sensor on Landsat 7 and that, "tides and ocean currents in the Bahamas sculpted the sand and seaweed beds into these multicolored, fluted patterns in much the same way that winds sculpted the vast sand dunes in the Sahara Desert."
An image as beautiful as this seemed like it deserved a bit more explanation, so I grabbed a recent (January 9, 2014) scene of the same area captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite. That image (below) shows a much broader view of the area. You can still see some details of the intricate network of dunes, but the MODIS image offers a much better sense of the regional geology. For instance, you can easily see that the section of dunes shown in the first image (the white box in the lower image) is part of a much larger limestone platform called the Great Bahama Bank. Limestone is a sedimentary rock formed by the skeletal fragments of sea creatures, including corals and foraminifera, and this particular limestone platform has been accumulating since at least the Cretaceous Period.
You can also see a sharp division between the shallow (turquoise) waters of the Great Bahama Bank and the much deeper (dark blue) parts of the ocean. The submarine canyon that separates Andros Island from Great Exuma Island is nearly cut off entirely from the ocean by the Grand Bahama Bank, but not quite. A connection to deep waters to the north gives the trench the shape of a tongue, earning the feature the name "Tongue of the Ocean." At its lowest point, the floor of the Tongue of the Ocean is about 14,060 feet (4,285 meters) lower than Great Bahama Bank. The shallowest (lightest) parts of the Grand Bahama Bank, in contrast, are just a few feet deep.
Tuesday, January 21, 2014
Do you know what the fastest growing Advanced Placement (AP®) course is? It’s AP Human Geography! Over 113,000 students took the APHG exam in 2013, up from 2,000 just 12 years ago, and there are an estimated 3,200 AP Human Geography teachers in the USA alone. That’s the good news! But the challenges are that (1) the scores on APHG are among the lowest of any AP exam, and (2) there is a growing demand for experienced geography educators who can effectively teach these courses. To help educators and their students gain key geography content, skills, and perspectives, Elmhurst College has designed a series of online courses specifically for secondary educators in a Graduate Certificate Program in Human Geography. This program focuses on teaching spatial concepts as well as basic themes, skills and perspectives of human geography and how to apply them in the classroom.
Playlist of videos created for one of the courses, on urban, economic, and population geography, here: