Fog formation appears to be controlled by a high-pressure system normally present off the West Coast throughout the summer, said James Johnstone, a postdoctoral researcher with the Joint Institute for the Study of the Atmosphere and Ocean at the UW.
“The behavior of that high-pressure cell is responsible for a lot of the weather phenomena we see on the coast,” he said. It can alter water temperature, ocean circulation, surface winds and other factors linked to coastal fog formation.
The fog decline could have negative effects on coastal forests that depend on cool and humid summers, but Johnstone, who presents his findings Monday (Dec. 13) at the American Geophysical Union annual meeting in San Francisco, hasn’t seen evidence of that yet.
In fact, climate models indicate that coastal fog should be increasing because of global warming, but he believes that is not happening because of strong influence exerted by regional circulation patterns related to the Pacific Decadal Oscillation. That climate phenomenon, centered in the North Pacific, has wide-ranging effects that last for years or even decades rather than for just a year or two.
“You would eventually expect to see significant effects on the coastal forests if the fog continues to decline,” he said.
Johnstone examined records from airports up and down the West Coast that have taken hourly readings on cloud height for the last 60 years. He looked closely at two stations in particular, Monterey on the central California coast and Arcata on the northern California coast, and found that their decline in fog and increase in temperature matched very closely despite being separated by about 300 miles. Both also reflected a great deal of variability.
“During a foggy summer you tend to have cool conditions along the coast and unusually warm temperatures in the interior,” Johnstone said, adding that during less foggy summers coastal areas tend to be warmer than usual and the interior is cooler.
Historically there have been stark temperature differences at times between the coast and areas just a short ways inland. But the differences have been shrinking in recent years, mostly because of rising coastal temperatures, he said. Cooler temperatures typically are located near sea level, and the warmer inland temperatures begin to show up at about 1,300 feet in elevation.
Johnstone found that the contrast between inland and coastal temperatures was much greater from 1900 to 1930 than during the last 60 years, indicating that summers on the coast were much foggier in the early 20th century.
But he notes that while coastal fog has generally declined, the data in general have shown consistent variability. For example, the Pacific Northwest, and Seattle specifically, had record fog frequency in the summer of 2010, and many places along the West Coast recorded their foggiest summer since 1991.
A next step in his work will be to understand the discrepancy between climate models and actual fog observations so that the factors involved in summer fog formation can be better understood.
For more information, contact Johnstone at 206-685-0317 or firstname.lastname@example.org.
Vince Stricherz | Newswise Science News
Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle
22.06.2018 | Technical University of Denmark
Polar ice may be softer than we thought
22.06.2018 | Eberhard Karls Universität Tübingen
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
25.06.2018 | Ecology, The Environment and Conservation
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences