Light absorption properties of brown carbon over the western Pacific region

2020 ◽  
Author(s):  
Shantanu Kumar Pani ◽  
Neng-Huei Lin ◽  
Chung-Te Lee ◽  
Sheng-Hsiang Wang
Keyword(s):  
Biomass Burning ◽  
Light Absorption ◽  
Radiative Forcing ◽  
Western Pacific ◽  
Pacific Region ◽  
Western Pacific Region ◽  
Brown Carbon ◽  
Near Ultraviolet ◽  
The Impact ◽  
The Western Pacific

<p>Brown carbon (BrC) is generally emitted during coal combustion, biomass burning, and the formation of secondary organic aerosols. BrC is an exceptional type of organic compound that absorbs the incoming solar radiation efficiently at near-ultraviolet wavelengths and can influence the direct radiative forcing estimates. Lulin Atmospheric Background Station (LABS, 23.47°N, 120.87°E; 2862 m above sea level) on the summit of Lulin Mountain in central Taiwan is the only high-altitude background station in the western Pacific region to study the impact of various long-range transported air pollutants. LABS usually receives the westerly winds coupled with biomass-burning emissions from peninsular Southeast Asia during the springtime. Aerosol measurements are carried out at LABS as a part of the Seven South East Asian Studies/Biomass-burning Aerosols & Stratocumulus Environment: Lifecycles & Interactions Experiment (7-SEAS/BASELInE) 2013 spring campaign. Light absorption coefficients are measured by the Aethalometer (AE 31, Magee Scientific, USA). Assuming a negligible contribution from dust, absorption solely due to BrC is estimated by subtracting the absorption of black carbon (BC) from total absorption. The relationships between BrC light absorption and carbonaceous fractions are investigated during the sampling period. The atmospheric radiative forcing due to BrC over the western Pacific region accounts for approximately 30% of that from BC. The detailed results will be presented.</p>

scholarly journals The impact of COVID-19 and the restoration of tuberculosis services in the Western Pacific Region

2020 ◽  
Vol 56 (4) ◽  
pp. 2003054
Author(s):  
Chen-Yuan Chiang ◽  
Tauhid Islam ◽  
Caihong Xu ◽  
Thilaka Chinnayah ◽  
Anna Marie Celina Garfin ◽  
...  
Keyword(s):  
Western Pacific ◽  
Pacific Region ◽  
Western Pacific Region ◽  
The Impact ◽  
The Western Pacific

scholarly journals Measurement Report: Optical properties and sources of water-soluble brown carbon in Tianjin, North China: insights from organic molecular compositions

2022 ◽  
Author(s):  
Junjun Deng ◽  
Hao Ma ◽  
Xinfeng Wang ◽  
Shujun Zhong ◽  
Zhimin Zhang ◽  
...  
Keyword(s):  
Optical Properties ◽  
Biomass Burning ◽  
Light Absorption ◽  
Radiative Forcing ◽  
North China ◽  
Water Soluble ◽  
Formation Mechanisms ◽  
Chemical Compositions ◽  
Brown Carbon ◽  
Near Ultraviolet

Abstract. Brown carbon (BrC) aerosols exert vital impacts on climate change and atmospheric photochemistry due to their light absorption in the wavelength range from near-ultraviolet (UV) to visible light. However, the optical properties and formation mechanisms of ambient BrC remain poorly understood, limiting the estimation of their radiative forcing. In the present study, fine aerosols (PM2.5) were collected during 2016–2017 on a day/night basis over urban Tianjin, a megacity in North China, to obtain seasonal and diurnal patterns of atmospheric water-soluble BrC. There were obvious seasonal but no evident diurnal variations in light absorption properties of BrC. In winter, BrC showed much stronger light absorbing ability since mass absorption efficiency at 365 nm (MAE365) (1.54 ± 0.33 m2 g−1), which was 1.8 times larger than that (0.84 ± 0.22 m2 g−1) in summer. Direct radiative effects by BrC absorption relative to black carbon in the UV range were 54.3 ± 16.9 % and 44.6 ± 13.9 %, respectively. In addition, five fluorescent components in BrC, including three humic-like fluorophores and two protein-like fluorophores were identified with excitation-emission matrix fluorescence spectrometry and parallel factor (PARAFAC) analysis. The lowly-oxygenated components contributed more to winter and nighttime samples, while more-oxygenated components increased in summer and daytime samples. The higher humification index (HIX) together with lower biological index (BIX) and fluorescence index (FI) suggest that the chemical compositions of BrC were associated with a high aromaticity degree in summer and daytime due to photobleaching. Fluorescent properties indicate that wintertime BrC were predominantly affected by primary emissions and fresh secondary organic aerosol (SOA), while summer ones were more influenced by aging processes. Results of source apportionments using organic molecular compositions of the same set of aerosols reveal that fossil fuel combustion and aging processes, primary bioaerosol emission, biomass burning, and biogenic and anthropogenic SOA formation were the main sources of BrC. Biomass burning contributed much larger to BrC in winter and at nighttime, while biogenic SOA contributed more in summer and at daytime. Especially, our study highlights that primary bioaerosol emission is an important source of BrC in urban Tianjin in summer.

scholarly journals Subtype H3N2 Influenza A Viruses: An Unmet Challenge in the Western Pacific

Vaccines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 112
Author(s):  
Min Kang ◽  
Mark Zanin ◽  
Sook-San Wong
Keyword(s):  
Influenza A ◽  
Vaccine Effectiveness ◽  
Western Pacific ◽  
Pacific Region ◽  
Western Pacific Region ◽  
Influenza A Viruses ◽  
Influenza A H1n1 ◽  
H3n2 Influenza ◽  
The Impact ◽  
The Western Pacific

Subtype H3N2 influenza A viruses (A(H3N2)) have been the dominant strain in some countries in the Western Pacific region since the 2009 influenza A(H1N1) pandemic. Vaccination is the most effective way to prevent influenza; however, low vaccine effectiveness has been reported in some influenza seasons, especially for A(H3N2). Antigenic mismatch introduced by egg-adaptation during vaccine production between the vaccine and circulating viral stains is one of the reasons for low vaccine effectiveness. Here we review the extent of this phenomenon, the underlying molecular mechanisms and discuss recent strategies to ameliorate this, including new vaccine platforms that may provide better protection and should be considered to reduce the impact of A(H3N2) in the Western Pacific region.

HTLV‐I infection in selected populations in Australia and the western Pacific region

1992 ◽  
Vol 156 (12) ◽  
pp. 878-880 ◽  
Author(s):  
Suellen R Nicholson ◽  
Theordora Efandis ◽  
Mary Dimitrakakis ◽  
Anna Karopoulos ◽  
Helen Lee ◽  
...  
Keyword(s):  
Western Pacific ◽  
Pacific Region ◽  
Western Pacific Region ◽  
The Western Pacific

scholarly journals Assessing the links between human rights and global tobacco control through statements made on global fora

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Neiloy R. Sircar ◽  
Stella A. Bialous
Keyword(s):  
Human Rights ◽  
Tobacco Control ◽  
Western Pacific ◽  
Global Health Governance ◽  
Pacific Region ◽  
Pacific Island ◽  
Western Pacific Region ◽  
Health Governance ◽  
Pacific Island Countries ◽  
The Western Pacific

Abstract Background Increasingly, international health bodies frame public health measures, including tobacco control, in the context of human rights (HR). It is unclear how prevalent is the connection between human rights and tobacco control within global health governance. This paper describes the inclusion of HR in tobacco control governance, and the inclusion of tobacco control in HR treaty oversight. We depict the current reach of HR’s normative influence in framing the tobacco epidemic in global, regional, and country-specific contexts. Methods We reviewed documents (agenda, reports) from 2010 to 2019 from the World Health Assembly (WHA); the WHO Western Pacific Regional Committee Meetings (RCM); the WHO Framework Convention on Tobacco Control (WHO FCTC) Conferences of the Parties (COP); and documents provided by Pacific Island Countries party to, or by committees overseeing, HR treaties. We purposively selected the Western Pacific Region, and Pacific Island Countries specifically, to represent countries of varying populations, capacities, and governance. Results Tobacco control and HR are infrequently mentioned together in the WHAs, and primarily in only one COP. Tobacco control is mentioned in 47 HR treaty committee documents for Pacific Island Countries, mostly under the Convention of the Rights of the Child recognizing or calling for ratification of the WHO FCTC. HR and tobacco control are connected in WHO Western Pacific RCM, particularly through their two most-recent action plans adopted by respective RCMs. Discussion Tobacco control as a HR concern is gaining traction within HR treaty bodies, at least with respect to children’s health in the Western Pacific Region. Conclusion Globally, HR is just emerging as an influence in global health governance for tobacco discussions. Within the Western Pacific Region however tobacco control is seen by some authorities as a HR issue. Similarly, to HR experts, tobacco control is becoming important to how Pacific Island Countries fulfill their treaty obligations, suggesting tobacco control advocates might explore these mechanisms to further influence the development of strong tobacco control measures to implement the WHO FCTC.

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