Back in 1973, a volcanic eruption in the western Pacific ocean caused the formation of a new island named Nishino-shima. Four months ago, a nearby eruption caused the formation of a new island named Niijima. The Niijima eruption has continued and the island has been growing and has now consumed Nishino-shima and it is continuing to grow larger.
The Niijima portion of the island is now larger than the original Nishino-shima, and the merged island is slightly more than 1,000 meters across. Two cones have formed around the main vents and stand more than 60 meters above sea level, triple the highest point of the island in December. Volcanic lava flows are reported to be most active now on the south end of the island.
Last weekend, rainfall triggered a massive landslide near Oso, Washington that killed at least 24 people. There have been many news reports about the event, but I believe NASA is the first to provide satellite imagery of the area post-landslide.
The imagery isn’t particularly sharp, but it shows the massive scale of the landslide. In addition, the landslide has blocked the Stillaguamish River, creating a barrier lake and flooding additional homes. While the timing is always unknown for events like this, the possibility has existed for years:
According to Durham University geologist Dave Petley, the landslide was a reactivation of an earlier landslide that caused problems in 1988 and 2006. The Seattle Times has reported that retired US. Geological Survey geologist Daniel Miller warned the hillside had the “potential for a large catastrophic failure” in a report filed with U.S. Corp of Engineers in 1999.
In the past 100 years, the Colorado River delta has gone from a very green area to quite brown and dead, thanks to huge demand on the water by the United States and Mexico. However, a plan is in place to generate an annual “pulse flow” from the Morelos dam in an effort to simulate a spring flood and help bring life back to the area.
The image above was captured back on March 8 of this year, showing Morelos dam and the surrounding area. You can view it in Google Earth by loading this KML file.
Researchers and water managers plan to track the changes using Landsat 8 and other satellite imagery to see how the area responds. Read more about this image and the “pulse” plan over on the NASA Earth Observatory site.