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.
AGING: As of last month, people aged 65 or older accounted for 20.06 percent of the total population and the number of couples who got married fell by 18,685 from 2024 Taiwan has surpassed South Korea as the country least willing to have children, with an annual crude birthrate of 4.62 per 1,000 people, Ministry of the Interior data showed yesterday. The nation was previously ranked the second-lowest country in terms of total fertility rate, or the average number of children a woman has in her lifetime. However, South Korea’s fertility rate began to recover from 2023, with total fertility rate rising from 0.72 and estimated to reach 0.82 to 0.85 by last year, and the crude birthrate projected at 6.7 per 1,000 people. Japan’s crude birthrate was projected to fall below six,
US President Donald Trump in an interview with the New York Times published on Thursday said that “it’s up to” Chinese President Xi Jinping (習近平) what China does on Taiwan, but that he would be “very unhappy” with a change in the “status quo.” “He [Xi] considers it to be a part of China, and that’s up to him what he’s going to be doing, but I’ve expressed to him that I would be very unhappy if he did that, and I don’t think he’ll do that. I hope he doesn’t do that,” Trump said. Trump made the comments in the context
SELF-DEFENSE: Tokyo has accelerated its spending goal and its defense minister said the nation needs to discuss whether it should develop nuclear-powered submarines China is ramping up objections to what it sees as Japan’s desire to acquire nuclear weapons, despite Tokyo’s longstanding renunciation of such arms, deepening another fissure in the two neighbors’ increasingly tense ties. In what appears to be a concerted effort, China’s foreign and defense ministries issued statements on Thursday condemning alleged remilitarism efforts by Tokyo. The remarks came as two of the country’s top think tanks jointly issued a 29-page report framing actions by “right-wing forces” in Japan as posing a “serious threat” to world peace. While that report did not define “right-wing forces,” the Chinese Ministry of Foreign Affairs was
PREPAREDNESS: Given the difficulty of importing ammunition during wartime, the Ministry of National Defense said it would prioritize ‘coproduction’ partnerships A newly formed unit of the Marine Corps tasked with land-based security operations has recently replaced its aging, domestically produced rifles with more advanced, US-made M4A1 rifles, a source said yesterday. The unnamed source familiar with the matter said the First Security Battalion of the Marine Corps’ Air Defense and Base Guard Group has replaced its older T65K2 rifles, which have been in service since the late 1980s, with the newly received M4A1s. The source did not say exactly when the upgrade took place or how many M4A1s were issued to the battalion. The confirmation came after Chinese-language media reported
RSS