James Kinter, director of the Center for Ocean-Land-Atmosphere Studies at the Institute of Global Environment and Society, presented this historical tidbit on the second morning of the recent XSEDE12 conference in Chicago.
then showcased the latest advances in climate and weather modeling enabled by the Extreme Science and Engineering Discovery Environment
(XSEDE), the National Science Foundation
(NSF)-supported cyberinfrastructure for open science.
"You might think there's a debate about climate change," Kinter
According to Kinter
, scientists have improved our understanding of the physical processes involved in atmospheric modeling and incorporated these insights into the evolving codes.
To test this, Kinter
colleagues simulated a variety of climate scenarios at resolutions ranging from 7 kilometers (the most fine-grained) to 125 kilometers (the most coarse-grained).
To accomplish this massive computing feat, Kinter's
team was granted a special allocation of computing time on the Athena supercomputer at the National Institute for Computational Sciences
(NICS) in 2009 and 2010.
This was "the smoking gun of whether humans are responsible for the rise in temperature," Kinter
However, the trends at regional scale are not as discernible.
Is that because the trends are not there or because the models lack the acuity to see them?
colleagues' investigations of high spatial resolution shed light on this question.
Other simulations explored the probability of extreme drought in the Midwest, Europe and elsewhere in the future.
estimates, the Midwest will experience the levels of extreme drought it is currently experiencing in 20 years out of every 50 - a four-fold increase.
"This drought will be the norm at the end of the 21st century," Kinter
said, "according to these simulations."
also presented a number of key examples where increases in model resolution impacted the clarity and content of results.
For instance, he
cited research by collaborators that showed how low-resolution models of the East Coast Gulf Stream put rain associated with the weather pattern in the wrong place, whereas high-resolution models delineate the bands of rain off the East Coast with accuracy.
After outlining the advantages of higher-resolution models, Kinter
elaborated on the challenges that such a change generates.
Biases in the models, the parameterization of small time and spatial scale effects (like clouds), and the coupling of global climate models with cloud resolving models, are all difficult, but not impossible, to overcome.
However, the primary challenge that Kinter's
group and the community are dealing with is the "exaflood of data" produced by high-resolution and highly complex coupled models.
For Project Athena, the total data volume generated and now resident at NICS
is 1.2 petabytes.
However, the total data volume on spinning disk at the Center for Ocean-Land-Atmosphere Studies for Project Athena
is capped at 50 terabytes.
This creates difficulties.
Running on TeraGrid systems at large-scale for the first time with so much data, "everything broke," Kinter
colleagues had to find ad hoc solutions to complete the simulations.
The next step, he
said, is to take those ad hoc solutions and use them to develop systematic, repeatable solutions.
Put another way: to deal with the exaflood, the community needs to progress from Noah's Ark to a professional shipping industry.
"We need exaflood insurance," Kinter