Satellite data study pinpoints areas sinking and rising along California coast
Tracking and predicting sea level rise involves more than measuring the height of our oceans: Land along coastlines also inches up and down in elevation. Using California as a case study, a NASA-led team has shown how seemingly modest vertical land motion could significantly impact local sea levels in coming decades.
Himalayas formation may have destroyed at least 30% of continental crust in collision zone
Earth's continents are slowly moving across the planet's surface due to plate tectonics, culminating in regions of crustal expansion and collision. In the latter case, high temperatures and pressures lead to the reworking of the crust, affecting its composition, as well as that of the underlying mantle. Furthermore, when two continental plates collide, distinct topographic features are produced, namely mountain ranges, which are surficial manifests of Earth's thickened crust.
Most detailed study yet of seismic activity links fault strength to likelihood of large earthquakes
Located on the Pacific Ring of Fire, Japan is one of the most earthquake-prone countries in the world, with thousands of small earthquakes occurring each year, and the continuous threat of a "big one." Currently, predicting when major earthquakes will occur isn't possible, but by studying the numerous small earthquakes that occur, seismologists in Japan hope to understand more about the processes in the Earth's crust that lead to major quakes.
Earthquake fault friction’s dependence on temperature different from previously thought
USC Dornsife Professor Sylvain Barbot discusses why his new study forces researchers to rethink the fundamental basis of the fault mechanics.
Moving mountains: reevaluating the elevations of Colorado mountain summits using modern geodetic techniques - Journal of Geodesy
One of the most challenging environments for accurate geoid models is in high, rugged mountain areas. Orthometric heights derived from GNSS and a geoid model can easily have errors at the decimeter level. To investigate the effect of geoid model variability on the elevations of peaks in high, rugged mountain areas, this paper is focused on the “Fourteeners” of Colorado, USA (a group of about 60 peaks that are above 14,000 feet = 4267.2 m). Airborne LiDAR data are used to determine geometric (ellipsoidal) heights, which first requires removing a hybrid geoid model, as the LiDAR data is originally provided as orthometric heights. We quantify a significant improvement when using these derived ellipsoidal heights compared with the original orthometric heights: from ± 0.074 to ± 0.054 m (RMSE), an improvement of 28%. Next, a mean geoid model is determined with a relative accuracy of ± 0.06 to 0.08 m and used as a “stand in” realization of the future, official geopotential datum of the USA, NAPGD2022. Using the LiDAR ellipsoidal heights and geoid model, elevations (and uncertainties) for each of the Fourteener summits are determined and found to be, on average, 1.6 m lower than currently published values. This is a much larger change than the 0.5 m decrease expected from the new datum shift alone. The bulk of the difference is due to the original treatments of the vertical angle, triangulation data. A reanalysis of 32 of the 60 peaks shows that the historic data were indeed too high by about 1.0 m or more. Ultimately, no peak falls below the 14,000-foot level nor are any peaks elevated above this level.
Researchers find the link between human activity and shifting weather patterns in western North America
Western North America seems to be experiencing more extreme weather events more frequently. From scorching droughts to torrential floods, the climate is changing rapidly, with no signs of slowing down. From 2011 to 2015, California and neighboring states experienced extended periods of drought, while 2017 saw heavy rains trigger catastrophic floods.
The Moon Has a Curious Effect on The Sounds Emanating From Coral Reefs
The Moon influences life here on Earth more than you might realize – and that includes shifting the sounds coming from coral reefs, which indicates changes in ecosystem activity, according to a new study.
Study Pinpoints Links Between Melting Arctic Ice and Summertime Extreme Weather in Europe - Inside Climate News
New research shows how last year’s warming melted ice in Greenland that increased flows of fresh, cold water into the North Atlantic, upsetting ocean currents in ways that lead to atmospheric changes.
💧🌏 Greg Cocks
