scholarly journals A New All-Season Passive Sampling System for Monitoring H2S in Air

2002 ◽  
Vol 2 ◽  
pp. 155-168 ◽  
Author(s):  
Hongmao Tang ◽  
James Sandeluk ◽  
Linda Lin ◽  
J. WIlliam Lown

A new Maxxam All-Season Passive Sampling system for monitoring H2S in air has been developed. This passive sampling system employs the same approaches as the Maxxam All-Season Passive Sampling Systems for monitoring SO2, NO2, and O3reported previously. This system has been extensively tested in the lab (temperature from -20 to 20°C, relative humidity from 30 to 84%, and wind speed from 0.5 to 150 cm/s) and validated in field studies. Comparing measurements obtained with the use of the new passive sampling system with equivalent measurement with the use of an active filter pack H2S sampler yielded an accuracy of greater than 85%. The new H2S passive sampling system can be used to measure ambient H2S concentrations ranging from 0.02 to 7 ppb based on a 1-month exposure period. There is no significant interference found from other sulfur compounds in air. This system has been used in many air monitoring projects.

2022 ◽  
Author(s):  
Suzanne Slack ◽  
Jeff Schachterle ◽  
Emma Sweeney ◽  
Roshni Kharadi ◽  
Jingyu Peng ◽  
...  

Populations of the fire blight pathogen Erwinia amylovora Ea110 on apple flower stigmas were tracked over the course of apple bloom in field studies conducted between 2016 and 2019. In 18 of 23 experiments, flower stigmas inoculated on the 1st day of opening were found to harbor large (106-107 cells / flower) populations of E. amylovora when assessed three to five days post-inoculation. However, populations inoculated on stigmas of flowers that were already open for three days did not reach 106 cells / flower, and populations inoculated on stigmas of flowers that were already open for five days never exceeded 104 cells / flower. During this study, >10-fold increases in E. amylovora stigma populations in a 24-hr time period (termed population surges) were observed on 34.8%, 20.0%, and 4.0% of possible days on 1-day, 3-day, and 5-day open flowers, respectively. Population surges occurred on days with average temperatures as high as 24.5°C and as low as 6.1°C. Experiments incorporating more frequent sampling during days and overnight revealed that many population surges occurred between 10:00 PM and 2:00 AM. A Pearson’s correlation analysis of weather parameters occurring during surge events indicated that population surges were significantly associated with situations where overnight temperatures either increased or remained constant, where wind speed decreased, and where relative humidity increased. This study refines our knowledge of E. amylovora population dynamics and further indicates that E. amylovora is able to infect flowers during exposure to colder field temperatures than previously reported.


2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Wanlin Dong ◽  
Chao Li ◽  
Qi Hu ◽  
Feifei Pan ◽  
Jyoti Bhandari ◽  
...  

Climate change has caused uneven changes in hydrological processes (precipitation and evapotranspiration) on a space-temporal scale, which would influence climate types, eventually impact agricultural production. Based on data from 61 meteorological stations from 1961 to 2014 in the North China Plain (NCP), the spatiotemporal characteristics of climate variables, such as humidity index, precipitation, and potential evapotranspiration (ET0), were analyzed. The sensitivity coefficients and contribution rates were applied to ET0. The NCP has experienced a semiarid to humid climate from north to south due to the significant decline of ET0 (−13.8 mm decade−1). In the study region, 71.0% of the sites showed a “pan evaporation paradox” phenomenon. Relative humidity had the most negative influence on ET0, while wind speed, sunshine hours, and air temperature had a positive effect on ET0. Wind speed and sunshine hours contributed the most to the spatiotemporal variation of ET0, followed by relative humidity and air temperature. Overall, the key climate factor impacting ET0 was wind speed decline in the NCP, particularly in Beijing and Tianjin. The crop yield in Shandong and Henan provinces was higher than that in the other regions with a higher humidity index. The lower the humidity index in Hebei province, the lower the crop yield. Therefore, potential water shortages and water conflict should be considered in the future because of spatiotemporal humidity variations in the NCP.


2010 ◽  
Vol 44 (13) ◽  
pp. 4917-4923 ◽  
Author(s):  
Sanford L. Britt ◽  
Beth L. Parker ◽  
John A. Cherry

2017 ◽  
Vol 56 (8) ◽  
pp. 2239-2258 ◽  
Author(s):  
Jonathan D. Wille ◽  
David H. Bromwich ◽  
John J. Cassano ◽  
Melissa A. Nigro ◽  
Marian E. Mateling ◽  
...  

AbstractAccurately predicting moisture and stability in the Antarctic planetary boundary layer (PBL) is essential for low-cloud forecasts, especially when Antarctic forecasters often use relative humidity as a proxy for cloud cover. These forecasters typically rely on the Antarctic Mesoscale Prediction System (AMPS) Polar Weather Research and Forecasting (Polar WRF) Model for high-resolution forecasts. To complement the PBL observations from the 30-m Alexander Tall Tower! (ATT) on the Ross Ice Shelf as discussed in a recent paper by Wille and coworkers, a field campaign was conducted at the ATT site from 13 to 26 January 2014 using Small Unmanned Meteorological Observer (SUMO) aerial systems to collect PBL data. The 3-km-resolution AMPS forecast output is combined with the global European Centre for Medium-Range Weather Forecasts interim reanalysis (ERAI), SUMO flights, and ATT data to describe atmospheric conditions on the Ross Ice Shelf. The SUMO comparison showed that AMPS had an average 2–3 m s−1 high wind speed bias from the near surface to 600 m, which led to excessive mechanical mixing and reduced stability in the PBL. As discussed in previous Polar WRF studies, the Mellor–Yamada–Janjić PBL scheme is likely responsible for the high wind speed bias. The SUMO comparison also showed a near-surface 10–15-percentage-point dry relative humidity bias in AMPS that increased to a 25–30-percentage-point deficit from 200 to 400 m above the surface. A large dry bias at these critical heights for aircraft operations implies poor AMPS low-cloud forecasts. The ERAI showed that the katabatic flow from the Transantarctic Mountains is unrealistically dry in AMPS.


2012 ◽  
Vol 610-613 ◽  
pp. 1033-1040
Author(s):  
Wei Dai ◽  
Jia Qi Gao ◽  
Bo Wang ◽  
Feng Ouyang

Effects of weather conditions including temperature, relative humidity, wind speed, wind and direction on PM2.5 were studied using statistical methods. PM2.5 samples were collected during the summer and the winter in a suburb of Shenzhen. Then, correlations, hypothesis test and statistical distribution of PM2.5 and meteorological data were analyzed with IBM SPSS predictive analytics software. Seasonal and daily variations of PM2.5 have been found and these mainly resulted from the weather effects.


Author(s):  
DA Narutdinov ◽  
RS Rakhmanov ◽  
ES Bogomolova ◽  
SA Razgulin

Introduction: Extreme climate conditions have a negative impact on human health. Purpose: The study aimed to assess weather and climate-related risks to human health in different areas of the Krasnoyarsk Region by effective temperatures estimated during two long-term observation periods. Materials and methods: We analyzed ambient temperatures (average monthly and minimum), wind speed (average and maximum), and relative humidity in the subarctic and temperate continental zones estimated during the periods of determining climatic norms in 1961–1990 and 1991–2020. The health risk was assessed on the basis of effective temperatures. Results: In the subarctic zone, the wind strength (average and maximum values) decreased, the duration of such periods increased just like the ambient temperature while the relative humidity did not change. In temperate climates, all indicators have changed. In the subarctic zone, in the second observation period, frostbite was possible within 20–30 minutes during two months (versus 3 in the first). In the temperate climate, there was no such risk to humans. At the minimum temperature and maximum wind speed in the subarctic zone, the risk of frostbite is possible during 5 months (versus 6): after 10–15 minutes during two months and after 20–30 minutes – during three months of the year. In temperate climates, frostbite is possible within 20–30 minutes during two months (versus 3 in the first period). Conclusions: In the interval of establishing climatic norms (1991–2020), a significant increase in effective temperatures was determined: in the subarctic zone with the average wind strength and temperature in February–April and June, with maximum wind and minimum temperature – in March–July; in temperate climates, in April and June, respectively. The duration of periods of health risks posed by cold temperature exposures in the subarctic climate with average wind and temperature values equaled two months (I–II), with maximum wind speed and minimum temperatures – five months (XI–III); in the temperate climate, it was null and 2 (3) months (I, II, and XII), respectively.


2021 ◽  
Vol 50 (1) ◽  
pp. 15-19
Author(s):  
Rakesh Punia ◽  
Pavitra Kumari ◽  
Anil Kumar ◽  
AS Rathi ◽  
Ram Avtar

Progression of Alternaria blight disease was measured on two susceptible Indian mustard varieties viz., RH 30 and RH 0749 sown at three different dates. The maximum increase in disease severity was recorded between first weeks of February and last week of February. During this period, the maximum and minimum temperature, relative humidity at morning and evening, average vapour pressure of morning and evening, maximum and bright sunshine hours and wind speed were higher, which resulted in congenial conditions for severe infection by the pathogen. The disease severity was positively correlated with maximum and minimum temperature, average vapour pressure, wind speed, sunshine hours and evaporation, while relative humidity and rainfall negatively correlated with Alternaria blight on both the varieties. A maximum value of area under disease progress curve was observed on cultivar RH 30 (651.1 cm2) as compared to RH 0749 (578.9 cm2), when crop was sown on 9th November.


2020 ◽  
Vol 27 (4) ◽  
pp. 98-102
Author(s):  
Haqqi Yasin ◽  
Luma Abdullah

Average daily data of solar radiation, relative humidity, wind speed and air temperature from 1980 to 2008 are used to estimate the daily reference evapotranspiration in the Mosul City, North of Iraq. ETo calculator software with the Penman Monteith method standardized by the Food and Agriculture Organization is used for calculations. Further, a nonlinear regression approach using SPSS Statistics is utilized to drive the daily reference evapotranspiration relationships in which ETo is function to one or more of the average daily air temperature, actual daily sunshine duration, measured wind speed at 2m height and relative humidity


2014 ◽  
Vol 119 (2) ◽  
pp. 584-593 ◽  
Author(s):  
Marion Benetti ◽  
Gilles Reverdin ◽  
Catherine Pierre ◽  
Liliane Merlivat ◽  
Camille Risi ◽  
...  

2013 ◽  
Vol 807-809 ◽  
pp. 20-23 ◽  
Author(s):  
Tao Sheng ◽  
Jian Wu Shi ◽  
Sen Lin Tian ◽  
Li Mei Bi ◽  
Hao Deng ◽  
...  

According to the information of air quality which published by the urban air quality real-time publishing platform, the concentration characteristics of PM10 and PM2.5 were studied in Kunming (KM), Changsha (CS), Hangzhou (HZ), Shanghai (SH), Harbin (HEB), Beijing (BJ), Wuhan (WH) and Guangzhou (GZ). The results show that the concentrations of PM10 and PM2.5 exceeded the Ambient Air Quality Standard (GB3095-2012) in varying degrees in March, 2013. The concentrations of PM10 in Wuhan is the highest, reached 164μg/m3, exceeded the standard by 9.3%; the concentrations of PM2.5 is much higher in Wuhan, Changsha and Beijing, the average concentrations were 96μg/m3, 103μg/m3 and 110μg/m3, exceeded the standard by 28.0%, 37.3% and 46.7% respectively. The correlation of PM10 with PM2.5 in most of these cities was good in March. The correlation analysis of pollutant with meteorological factor in Hangzhou, Shanghai, Beijing and Guangzhou was also studied, the results show that the concentrations of PM10 and PM2.5 are weakly positive correlation with temperature in the four cities, negative correlation with relative humidity without Beijing, and negative correlation with wind speed.


Sign in / Sign up

Export Citation Format

Share Document