New research suggests that air pollution indirectly reduces the amount of rainfall in northern Taiwan during autumn, which might have exacerbated the water shortage at New Taipei City’s Shihmen Reservoir (石門水庫).
Researchers from National Central University (NCU) and the State University of New York at Albany analyzed 13 years of satellite and surface data for the study, which was published on March 23 in the journal Atmospheric Chemistry and Physics.
Taiwan receives most of its annual rainfall from May to September during the plum rain and typhoon seasons, NCU Department of Atmospheric Sciences associate professor Wang Sheng-hsiang (王聖翔) said.
Photo courtesy of National Central University
Although there is relatively less rainfall during fall and winter, it is key to maintaining reservoir levels, Wang said.
However, it is also when pollution tends to be most severe, which not only affects health, but can also affect the characteristics of rain droplets, he added.
Researchers analyzed data from 2005 to 2017 on concentrations of PM2.5 — airborne particulate matter smaller than 2.5 micrometers — meteorological parameters, such as wind direction and temperature, raindrop size, aerosols and cloud properties, to determine the effect that aerosols might have on clouds and drizzle during autumn over northern Taiwan.
They found that in the densely industrialized northwest, the season is mainly dominated by warm, thin and broken clouds, which are defined as having an internal temperature of at least 0°C.
Aerosols were discovered to have an indirect effect on the clouds, meaning that as aerosol concentrations rose, cloud droplets became smaller and more numerous, with drizzles occurring less frequently.
The data also reflected this, as “polluted” days saw about 6.8mm less daily average rainfall than “clean” days, with polluted days defined as the 80th percentile of daily average PM2.5, while clean days fell in the 20th percentile.
Lead author of the study, Chen Ying-chieh (陳映潔), obtained a graduate degree from NCU’s Department of Atmospheric Sciences.
As a graduate student, she was in the first cohort of the US-Taiwan Partnership for International Research and Education (PIRE), which sent her on a two-month exchange to the US.
PIRE is run by the Ministry of Science and Technology and the US National Science Foundation through NCU and the State University of New York at Albany. The program aims to promote research collaboration on weather and climate prediction, and emergency response strategies.
Authorities have detained three former Taiwan Semiconductor Manufacturing Co (TMSC, 台積電) employees on suspicion of compromising classified technology used in making 2-nanometer chips, the Taiwan High Prosecutors’ Office said yesterday. Prosecutors are holding a former TSMC engineer surnamed Chen (陳) and two recently sacked TSMC engineers, including one person surnamed Wu (吳) in detention with restricted communication, following an investigation launched on July 25, a statement said. The announcement came a day after Nikkei Asia reported on the technology theft in an exclusive story, saying TSMC had fired two workers for contravening data rules on advanced chipmaking technology. Two-nanometer wafers are the most
NEW GEAR: On top of the new Tien Kung IV air defense missiles, the military is expected to place orders for a new combat vehicle next year for delivery in 2028 Mass production of Tien Kung IV (Sky Bow IV) missiles is expected to start next year, with plans to order 122 pods, the Ministry of National Defense’s (MND) latest list of regulated military material showed. The document said that the armed forces would obtain 46 pods of the air defense missiles next year and 76 pods the year after that. The Tien Kung IV is designed to intercept cruise missiles and ballistic missiles to an altitude of 70km, compared with the 60km maximum altitude achieved by the Missile Segment Enhancement variant of PAC-3 systems. A defense source said yesterday that the number of
A bipartisan group of US representatives have introduced a draft US-Taiwan Defense Innovation Partnership bill, aimed at accelerating defense technology collaboration between Taiwan and the US in response to ongoing aggression by the Chinese Communist Party (CCP). The bill was introduced by US representatives Zach Nunn and Jill Tokuda, with US House Select Committee on the Chinese Communist Party Chairman John Moolenaar and US Representative Ashley Hinson joining as original cosponsors, a news release issued by Tokuda’s office on Thursday said. The draft bill “directs the US Department of Defense to work directly with Taiwan’s Ministry of National Defense through their respective
Tsunami waves were possible in three areas of Kamchatka in Russia’s Far East, the Russian Ministry for Emergency Services said yesterday after a magnitude 7.0 earthquake hit the nearby Kuril Islands. “The expected wave heights are low, but you must still move away from the shore,” the ministry said on the Telegram messaging app, after the latest seismic activity in the area. However, the Pacific Tsunami Warning System in Hawaii said there was no tsunami warning after the quake. The Russian tsunami alert was later canceled. Overnight, the Krasheninnikov volcano in Kamchatka erupted for the first time in 600 years, Russia’s RIA
RSS