Research provides better understanding of long-term changes in the climate system

December 02, 2010

For more than a decade, Dr. Joseph Ortiz, associate professor of geology at Kent State University and part of an international team of National Science Foundation (NSF)-funded researchers, has been studying long-term climate variability associated with El Niño. The researchers' goal is to help climatologists better understand this global climate phenomenon that happens every two to eight years, impacting much of the world.

El Niño is the periodic warming of central and eastern tropical Pacific waters. The last El Niño occurred in 2009, Ortiz said, and its impact was felt in the United States with flooding in the south and wildfires in California. The research team looked at El Niño-Southern Oscillation (which is often just called "El Niño"), reconstructing sea surface temperature of the equatorial Pacific over the past 14,000 years.

"If we understand how El Niño changes over thousands of years, we can better predict climate changes on societal time-scales of years to decades," Ortiz explained. "El Niño variations lead to drought, famine, landslides, fires and other natural disasters, depending on where in the world you happen to be. Our findings can help lead to better ways to predict El Niño-Southern Oscillations, mitigating the natural disasters associated with it."

In addition to Ortiz, the research team includes the lead author on the paper, Thomas Marchitto (University of Colorado); Raimund Muscheler (Lund University in Sweden); Jose Carriquiry (Universidad Autónoma de Baja California, Ensenada in Mexico); and Alexander van Geen (Lamont-Doherty Earth Observatory of Columbia University). Their findings will appear in the Dec. 3 issue of Science, the prestigious journal published by AAAS, the world's largest science society. Their paper, "Dynamical Response of the Tropical Pacific Ocean to Solar Forcing During the Early Holocene," helps to establish the linkage between changes in solar intensity and the strength of El Niño on millennial time scales. Their work was funded by the Marine Geology Subdivision of the National Science Foundation's Ocean Sciences Division.

"The climate system is very sensitive to subtle external forcing," Ortiz said. "We determined that the sun has an impact but is not the sole factor driving changes on these millennial time scales. Other studies have tried to show a solar linkage to El Niño-related climate variability, but our study indicates a convincing linkage due to the continuity of our record. This paper confirms the 'ocean dynamical thermostat' theory, showing that solar-forced changes in ocean circulation have on impact on El Niño."

Ortiz began working with the international team of scientists when he was a post-doctoral scientist at Lamont-Doherty Earth Observatory, a research branch of Columbia University. Over the last 11 years, his contributions to the team include assisting with measurements and in the statistical analysis of the data sets. As a researcher in the Kent State geology department, Ortiz has involved Kent State graduates and undergraduates in his NSF-funded research, providing his students with real-world experience on an international level. His students have participated in research projects as close to home as here in Ohio, and as far away as the South Pacific, North Atlantic, Arctic, Pacific Northwest, and off Baja California.

"With my involvement in this project, Kent State geology students have studied core samples collected off of Baja California," Ortiz said. "The students can take what they learn in the classroom out into the field and back to the lab. I feel very fortunate to be able to provide our students with this type of experience and bring international-level research to Kent State."
-end-
Ortiz has been with Kent State since 2001. He resides in Hudson, Ohio.

For more information about Kent State's Department of Geology, visit www.kent.edu/geology.

Media Contacts:
Joseph Ortiz, jortiz@kent.edu, 330-672-2225
Emily Vincent, evincen2@kent.edu, 330-672-8595

Kent State University

Related Natural Disasters Articles from Brightsurf:

Natural disasters must be unusual or deadly to prompt local climate policy change
Natural disasters alone are not enough to motivate local communities to engage in climate change mitigation or adaptation, a new study from Oregon State University found.

When natural disasters strike locally, urban networks spread the damage globally
Disasters that occur in one place can trigger costs in cities across the world due to the interconnectedness of the global urban trade network.

Model can predict hospital resilience for natural disasters, pandemics
CSU researchers have created a modeling tool that could help cities understand the full functionality and recovery of a healthcare system in the wake of a natural disaster.

Wikipedia, a source of information on natural disasters biased towards rich countries
This is the result of a study led by Valerio Lorini, a PhD student on the ICT programme, led by Carlos Castillo, coordinator of the Web Science and Social Computing group, with Javier Rando, a student at UPF doing the bachelor's degree in Mathematical Engineering in Data Science, focusing on flooding as a case study.

Costs of natural disasters are increasing at the high end
While the economic cost of natural disasters has not increased much on average, averages can be deceptive.

When natural disasters strike, men and women respond differently
Women tend to take cover or prepare to evacuate sooner, but often have trouble convincing the men in their life to do so, suggests a new study exploring how gender influences disaster response.

Earthquakes, hurricanes and other natural disasters obey same mathematical pattern
Researchers from the Centre for Mathematical Research (CRM) and the Universitat Autònoma de Barcelona have mathematically described the frequency of several dangerous phenomena according to their size with more precision than ever.

In disasters, Twitter influencers get out-tweeted
A first-of-its-kind study on Twitter use during 5 of the costliest US natural disasters offers potentially life-saving insights.

Organizations with broad social ties help recovering from natural disasters
In order to encourage a wide economic recovery following a natural disaster, communities should think about activating advocacy organizations such as local environmental groups, political organizations and human-rights groups.

Study: Culture strongly influences coping behaviors after natural disasters
Demographic and cultural differences strongly influence the coping styles young people use when they're affected by a natural disaster, and these disparities should be taken into account when providing services to help them recover from these traumatic experiences, University of Illinois social work professors Tara M.

Read More: Natural Disasters News and Natural Disasters Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.