ges such as these can help document changes to the landscape, as alternative power sources are being developed to provide renewable energy for the Earth’s growing population.
Wind Power in Texas, United States January 20, 2015
Wind power is produced by using large generators to harness the kinetic energy of wind. It is gaining importance as a large-scale source of renewable energy, and new wind farms are being developed worldwide.
In the Texas Panhandle of the United States, an area previously known for fossil fuel production is undergoing a rapid surge in wind energy development. One example is the Longhorn North Wind Project, which was initiated in late 2013 and expected to be fully operational in 2015. When completed, the installation will provide approximately 200 megawatts of power from 100 wind turbines. The area covers almost 57 square kilometers (22 square miles), and is only one of many new wind farms that are being developed in this region of Texas.
These two images show the Longhorn North Wind Project area in December 2013 and one year later in December 2014. The irregular white lines in the later image are access roadways that support construction of the new wind turbines and connection to major transmission networks in the area. The small bright dots on those roadways represent individual turbine locations.
Another change in the later image is an increased number of green fields and small lakes filled with water. In September 2014, remnants from a tropical storm brought heavy rain to this part of Texas, which had been in a drought since 2011.
As wind energy sources continue to expand in the United States and worldwide, Landsat imagery will be useful for monitoring the land changes associated with this development. The consistent, repetitive images from Landsat can also provide a valuable record of the weather- and climate-induced influences as they occur on the Earth’s landscape.
The Sampson Flat Fire started on January 2, 2015 near Adelaide, Australia. Hot, windy weather during the Australian summer caused the bushfire to spread quickly and move erratically. By January 7, it had burned over 120 square kilometers (46 square miles) of woodland and grassland within the steep and inaccessible terrain of the Mount Lofty Ranges.
In the Landsat 8 image acquired on January 4, the burned areas are brown. Active fire appears red with white-blue smoke rising from it. The urban area of Adelaide can be seen in the lower left.
As of January 9, the fire has been contained, but firefighters continue to monitor the unburned pockets of vegetation for flare-ups. Falling trees and limbs have become a hazard for crews working in the area.
Multiple Storms along the Vietnam Coastline December 23, 2014
In July 2014, rains from Typhoon Rammasun triggered heavy flooding as it made landfall in northern Vietnam. Only two months later, Typhoon Kalmaegi made landfall along the same section of coast. While the rainfall was not as strong as it was from Rammasun, rivers were still swollen from the previous storm.
The first two Landsat images show the shoreline along the Gulf of Tonkin after each of these major storms. In the July image, the dark shades across the landscape indicate the extent of flooded land and potential crop damage due to Typhoon Rammasun. Increased flows of river sediment into the gulf are prominent in this image; bright shades of blue contrast with the surrounding waters.
The second image was acquired several days after Typhoon Kalmaegi made landfall. This image shows a less pronounced flood impact across the landscape, but sediment flows are still clearly visible from this storm. The October image shows the area in continued recovery after both typhoons, with normalized sediment flows into the gulf.
Landsat data provide an important source of pre- and post-event images that are often used to support disaster and recovery monitoring worldwide.
Ohio’s capital city, Columbus, is situated along the Scioto River and is one of the fastest growing cities in the state. In 1986, the municipal population was estimated at 600,00