March 2014 - Cooperative Institutes

CINAR Researchers Deploy Automated Plankton Microscopy on Recent EcoMon Survey

The journal, Atmospheric Chemistry and Physics, just published results of a recent experiment examining two stratosphere-to-troposphere (STT) events observed over California. NOAA/NESDIS researchers at the Cooperative Institute for Meteorological Satellite Studies (CIMSS), University of Wisconsin-Madison, are collaborating with NASA scientists, university researchers and air quality and public health scientists to analyze airborne and in situ measurements of ozone and other trace gases that accompany STT events. STT events are of concern because the ozone may increase to dangerous levels, triggering public health warnings.

Background: On June 6, 2012, a day after one of the California flights, State of Wyoming surface monitors recorded high levels of tropospheric ozone around Thunder Basin, Wyoming. Increased levels of tropospheric ozone are usually caused by anthropogenic sources such as smog, but on occasion a naturally occurring, downward transport of stratospheric air can push tropospheric ozone to unsafe levels. On June 6, Thunder Basin region ozone concentrations spiked at nearly 100 parts per billion (ppb), well above the 75 ppb public health standard established by the Environmental Protection Agency (EPA).

The researchers used the Real-time Air Quality Modeling System (RAQMS), a global forecast model that assimilates ozone observations from multiple satellite instruments, along with in situ airborne measurements from NASA, to facilitate data interpretation and determine the source of the high ozone. The experiment improved understanding of the transport of ozone from Pacific weather systems to Wyoming.

Using the evidence gathered by this team, the State of Wyoming Department of Environmental Quality filed a report with the EPA, documenting Thunder Basin ozone levels as an “exceptional event,” and the result of a natural occurrence; not pollution.

Significance: The just-published California study is an important continuation of research on methods to identify and interpret STTs. The studies have implications for air quality, policy, and public health decision makers. This work supports NOAA’s mission of “understanding and predicting changes in climate and weather and sharing that knowledge and information with others.”

Summary

Antarctic’s Siren Call: The Sound of Icebergs

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Antarctic’s Siren Call: The Sound of Icebergs

Scientists at the Cooperative Institute for Marine Resources Studies (CIMRS) are investigating sounds generated by icebergs in the Southern Ocean and their potential to affect marine animals and ecosystems. While the steady increase in global shipping traffic has been identified as a primary cause of rising ocean noise level, the disintegration of large icebergs was found to be another significant noise source that influences the soundscape of the southern hemisphere.

Background

Two icebergs, B15a and C19a, collectively larger than Connecticut, calved off the Ross Ice Shelf in early 2000s and drifted eastward to the warmer South Pacific Ocean in late 2007. For the next 1.5 years, while these icebergs were rapidly melting, they affected water circulation and marine ecosystem in their vicinity.

From 2008 to early 2009, the disintegration of B15a and C19a continuously projected loud low frequency sounds into the water column. The sounds propagated efficiently to lower latitudes, thus influencing the soundscape of the entire South Pacific basin. The icebergs’ sounds were recorded at Juan Fernandez Island (34^oS, 79^oW) by hydrophones maintained by Comprehensive Nuclear-Test-Ban Treaty Organization. The sounds also propagated across the equator (~10,000 km) and were recorded at 8^oN, 110^oW by a hydrophone maintained by NOAA Pacific Marine Environmental Laboratory (PMEL) and CIMRS. The noise level was ~7 dB and ~3 dB higher than baseline years, respectively. The icebergs’ sounds dominated frequency ranges below 100 Hz in which marine mammals, such as baleen whales, vocalize for communication, navigation and forage behaviors.

Significance

Some large icebergs have lifespans over a decade. This study shows that icebergs the size of B15a and C19a can generate a considerable amount of sound energy, which can propagate across ocean basins, influencing the ocean acoustic environment and potentially marine mammals’ acoustic behaviors for the duration of the iceberg’s disintegration.

The study meets NOAA PMEL’s goals of (a) to acquire long-term data sets of the global ocean acoustics environment and (b) to identify and assess acoustic impacts from human activities and natural processes on the marine environment.

Contact: Haru Matsumoto, Oregon State University CIMRS Assistant Professor, Research, matsumoh@onid.oregonstate.edu

Summary

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