Tuesday, September 29, 2015

Ice melt in the Arctic

Here is a link to an awesome Youtube video produced by NASA
https://www.youtube.com/watch?v=UUoTDL99Mb4&feature=youtu.be

 ...that looks at quantifying lake depth using remote sensing.

https://nsidc.org/gallery/coppermine/displayimage.php?album=27&pos=146
is an image of the Greenland ice sheet taken from a helicopter in 2004 by one of the NSIDC researchers that also shows the differentiation of blue colors.

What Dr. Allen Pope is looking at in the first video is data from the Landsat 8 satellite.  He's analyzing the blue in the lakes in order to determine depth.  Darker lakes mean deeper lakes. This is important information because an increase in melt creates a positive feedback loop where the ice continues to melt at a faster and faster pace.  As more water pools, more light is absorbed and the ice sheet disapears even quicker.  Specifically, monitoring glacial melt is one way to quantify global warming.  We have almost 40 years of satellite data observing the ice melt in Greenland and trends show that its been steadily getting smaller since we started collecting imagery in 1978. It is all done with remote sensing.

This all came up because September 11th, 2015, was the Actic sea ice minimum, and the fourth smallest ice minimum ever.  Here is a Washington post article with links to some NASA images of the entire icemelt.

https://www.washingtonpost.com/blogs/capital-weather-gang/wp/2015/09/17/september-11-arctic-sea-ice-minimum-the-4th-lowest-on-record-in-five-visuals/

Ice is pretty neat.

Posted by Teague Walsh-Felz

Dubai's artificial islands

The first image is a larger scale image of "The World", which is a collection of artificial islands constructed off of the coastline of Dubai.  The design of the islands roughly mimics the view of the Earth's continents from space.  The second image is smaller scale so it also captures the "Palm" islands. 

The construction of these islands was a feat of modern engineering but they have also been criticized for potentially harming the local aquatic environment.  The logic of investing billions of dollars to create a small amount of new land that is barely above sea level is also questionable. 

http://news.mongabay.com/2006/10/satellite-photo-of-dubais-artificial-islands-the-world-and-the-palms/

















Posted by Steve Vosberg

Thursday, September 17, 2015

California Drought

California's drought problem today is one of the worst droughts that the state, or even country, has ever seen. Since this summer, when all California residents were told to significantly limit their water by cutting their consumption rate by 15%. But this is just the start of the problem, NASA and Cornell and Columbia scientists predict that California and the rest of the Southwest would go into a 30-year long drought by 2050 if the greenhouse gas emissions are not cut or lowered significantly. This would be a huge problem not only for California and the Southwest but for the entire country if it were to happen! 
In the first image that WashPo provides it shows the arid landscape that has come about because of the drought. So in this photo one can see that the river that is cutting through the image has shrunk immensely in size. One can tell this from where the river is touching the banks now and where the banks originally were when the water level was higher. One can tell that the water level is draining fast because the banks is still darker from where the water line was not too long ago. One can also tell the barren, arid land because of the shape and pattern of the trees and bushes which are spaced out to resemble what would normally be a forest layout, but since there isn't any ground cover, it looks like its in a desert area. By the texture of the trees and bushes one can tell that are spiky and less covered in leaves and vegetation than normal, also telling us that this land is part of drought land. This is such an important image to see because it really shows how low the water level is comparative to what it used to be and would serve as a great propaganda piece to recruit climate change activists, especially if they lived in the Southwest or in California.

Here is the image (if it doesn't appear on the site): 

Tuesday, September 15, 2015

2014 Israel-Gaza Conflict

The New York Times's coverage of Israel's invasion of Gaza included helpful uses of satellite imagery. If you scroll down to "Shejaiya" and use the slider to toggle between before and after conflict began, you can see its impact. In particular, look east of the city in the before image. The regular pattern (with homogenous texture) of thin green rectangles (different shades of green) suggests productive agriculture. In the after image, the green is gone, replaced by browns - the pattern is gone too, with much more variation, suggesting disruption. There are however regular strips of light brown stemming from the west that, in association with the border, suggest the movement of troops in Gaza. In my opinion, the image is too small scale to be able to discern much in the way of impact to structures.

Thursday, September 10, 2015

Hurricane season in the Atlantic

The imagery shows somewhere in Caribbean Sea with a large hurricane clouds, that is almost scary to us who remember Hurricane Katrina, and Sandy.  It is used in unreal story, but the image must be taken from a real remote sensing photo from a satellite.

http://www.theonion.com/article/meteorologists-say-upcoming-hurricane-season-be-pe-51246

The imagery is not important in scientific sense because it is used for an article in the Onion, a newspaper filled with jokes and untrue stories.  However, if you have a sense of humor and thoughts on why humans make jokes and be sarcastic sometimes, you would understand this article with the eye-catching imagery tells us something.  Due to climate change, we are encountering stronger and more devastating hurricanes, droughts, regional downpours, and other unusual weather patterns.  It might become true that we may have many more hurricanes this fall than in the past.  Compared to Mother Nature's strength, we humans are so helpless often, which is described by the metaphor of needing candles, even in this electronics age.  Coast lines mentioned in the article keep retrieving due to sea level rise.  And it seems that we are having more large-scale earthquakes, which must not be related to climate change, but makes us think of the environment and the Earth system.

So, this joke article is not truth, but has its own value to make us realize climate change is man-made.  


Posted by Masami Glines

Sea-level rise in Louisiana

The USGS says sea-level rise and sinking could claim up to 4,677 square miles of land along the coast if the state doesn’t implement major restoration plans.
 

This website by ProPublica is a longform interactive piece on the loss of Louisiana's coastline. It is not just one image, but rather a series of images in multiple places that tells the powerful story of land loss over the last 80 years. The most compelling use of aerial/satellite imagery on this website is the comparison of imagery over time. Because the land loss happened incrementally, locals did not notice that it was happening as the years went by. But comparing photos over time, it is easy to see how drastic the changes are; it is almost as if you can see the land sinking. The satellite imagery highlights the importance of taking measures to prevent the Louisiana coast from completely disappearing due to erosion and rising sea levels.
















http://projects.propublica.org/louisiana/


Posted by Robin Tolochko

Temple of Bel, Syria

The image shows the destruction of 2000-old Roman temples in Palmira, Syria. Anthropologists and scientists from the world were afraid that this event might happen. Several days ago, videos of the event were distributed on the internet, but since the scientists could go to corroborate (or prevent their destruction), only through satellite imagery, they found out that the temples were, in fact, destroyed.


http://www.theguardian.com/world/2015/sep/01/satellite-images-reveal-isis-destruction-of-palmyras-temple-of-bel

Residents have been slaughtered, and the archeologist, Khaled el-Assad, whom had been studied and protected the temples (the whole area), was decapitated, days before, by terrorists (ISIS). 

Posted by Ana Wells