Sea rise off coasts of Philippines, northeastern Australia rising at about 1 centimeter per year
A new study led by Old Dominion University and the University of Colorado Boulder indicates sea levels likely will continue to rise in the tropical Pacific Ocean off the coasts of the Philippines and northeastern Australia as humans continue to alter the climate.
The study authors combined past sea level data gathered from both satellite altimeters and traditional tide gauges as part of the study. The goal was to find out how much a naturally occurring climate phenomenon called the Pacific Decadal Oscillation, or PDO, influences sea rise patterns in the Pacific, said Assistant Professor Benjamin Hamlington of Old Dominion University in Norfolk, Va., a former CU-Boulder postdoctoral researcher and lead study author.
The PDO is a temperature pattern in the Pacific Ocean akin to El Niño but which lasts roughly 20 to 30 years and contributes significantly to the decadal trends in regional and global sea level, said CU-Boulder Research Professor Robert Leben, a study co-author. The research team performed sea level reconstructions going back to 1950 by fitting patterns of satellite altimeter data to tide gauge data, then stripped away the effects of the PDO to better understand its influence on current sea level increases in the Pacific.
"The conventional wisdom has been that if the Pacific Decadal Oscillation was removed from the equation this sea level rise in parts of the Pacific would disappear," said Hamlington, who received his doctorate from CU-Boulder. "But we found that sea level rise off the coasts of the Philippines and northeastern Australia appear to be anthropogenic and would continue even without this oscillation."
A paper on the subject was published online in the July 20 issue of Nature Climate Change. Other co-authors on the study included CU-Boulder doctoral student Matthew Strassburg, CU-Boulder Associate Professor Weiqing Han, CU-Boulder Professor R. Steven Nerem and Seoul National University faculty member K.Y. Kim. The study was funded primarily by NASA and the National Science Foundation.
The team also used NASA climate models to assess sea level rise in the tropical Pacific that included data on the warming tropical Indian Ocean, which has been shown in previous studies to be caused by increases in greenhouse gases. The climate modeling portion of the new study also showed sea level rise near the Philippines and Australia is caused at least in part by anthropogenic, or human-caused, warming said Hamlington, who got his doctorate under Leben.
The research team estimated that areas of the ocean near the Philippines and northeast Australia are being raised by about 1 centimeter per year due to anthropogenic warming, which can increase the intensity of severe weather. "When water starts piling up there and typhoon-like storms are traveling over higher sea levels, it can be a bad situation," said Hamlington.
Although global sea level patterns are not geographically uniform -- sea level rise in some areas correlate with sea level fall in other areas -- the average current global sea level rise is roughly 3 millimeters per year. Some scientists are estimating global seas may rise by a meter or more by the end of the century as a result of greenhouse warming.
"When the current PDO switches from its warm phase to its cool phase sea levels on the western coast of North America likely will rise," said Leben of CU-Boulder's aerospace engineering sciences department. "I think the PDO has been suppressing sea level there for the past 20 or 30 years."
In a broader sense, the new study shows that scientists may be able to look at other regions of the world's oceans and extract the natural climate variability in order to measure human-caused effects, said Hamlington, a researcher at CU-Boulder's Cooperative Institute for Research in Environmental Sciences. "This kind of research may start revealing patterns that we might not expect."
Most of the satellite altimeter data for the study came from NASA's Topex-Poseidon and Jason satellite series missions. Satellite altimetry measures sea level rise by bouncing radar pulses off the surface of the ocean at particular points and calculating the round-trip time it takes the pulse to return to the spacecraft said Leben, also a faculty member of CU-Boulder's Colorado Center for Astrodynamics Research, or CCAR.
A 2010 study led by CU-Boulder's Han published in Nature Geoscience concluded that greenhouse gases were responsible for rising seas in parts of the Indian Ocean. The changes are believed to be at least partially a result of the roughly 1 degree Fahrenheit increase in the Indo-Pacific warm pool -- an enormous, bathtub-shaped area stretching from the east coast of Africa to the International Date Line in the Pacific -- during the past 50 years.
For more information on CU-Boulder's aerospace engineering sciences department visit http://www.colorado.edu/aerospace/. For more information on CCAR visit http://www.colorado.edu/aerospace/research/colorado-center-astrodynamics-research. For more information on CIRES visit http://cires.colorado.edu/index.html.
Benjamin Hamlington, 303-735-0483
Robert Leben, 303-492-4113
Jim Scott, CU-Boulder media relations, 303-492-3114
Robert Leben | Eurek Alert!
Climate study finds human fingerprint in Northern Hemisphere greening
30.06.2016 | DOE/Oak Ridge National Laboratory
NASA sees heavy rain in Arabian Sea tropical cyclone
30.06.2016 | NASA/Goddard Space Flight Center
Since the completion of the human genome an important goal has been to elucidate the function of the now known proteins: a new molecular method enables the investigation of the function for thousands of proteins in parallel. Applying this new method, an international team of researchers with leading participation of the Technical University of Munich (TUM) was able to identify hundreds of previously unknown interactions among proteins.
The human genome and those of most common crops have been decoded for many years. Soon it will be possible to sequence your personal genome for less than 1000...
3D printing revolutionized the manufacturing of complex shapes in the last few years. Using additive depositing of materials, where individual dots or lines...
R2D2, a joint project to analyze and development high-TRL processes and technologies for manufacture of flexible organic light-emitting diodes (OLEDs) funded by the German Federal Ministry of Education and Research (BMBF) has been successfully completed.
In contrast to point light sources like LEDs made of inorganic semiconductor crystals, organic light-emitting diodes (OLEDs) are light-emitting surfaces. Their...
High resolution rotational spectroscopy reveals an unprecedented number of conformations of an odorant molecule – a new world record!
In a recent publication in the journal Physical Chemistry Chemical Physics, researchers from the Max Planck Institute for the Structure and Dynamics of Matter...
Strands of cow cartilage substitute for ink in a 3D bioprinting process that may one day create cartilage patches for worn out joints, according to a team of engineers. "Our goal is to create tissue that can be used to replace large amounts of worn out tissue or design patches," said Ibrahim T. Ozbolat, associate professor of engineering science and mechanics. "Those who have osteoarthritis in their joints suffer a lot. We need a new alternative treatment for this."
Cartilage is a good tissue to target for scale-up bioprinting because it is made up of only one cell type and has no blood vessels within the tissue. It is...
30.06.2016 | Event News
28.06.2016 | Event News
09.06.2016 | Event News
30.06.2016 | Health and Medicine
30.06.2016 | Life Sciences
30.06.2016 | Physics and Astronomy