Temperature Inversions and Off-Target Movement of Herbicides

2019 ◽  
Keyword(s):  
Target Movement ◽  
Temperature Inversions

scholarly journals Survey of Missouri Pesticide Applicator Practices, Knowledge, and Perceptions

2017 ◽  
Vol 31 (2) ◽  
pp. 165-177 ◽  
Author(s):  
Mandy D. Bish ◽  
Kevin W. Bradley
Keyword(s):  
Mail Survey ◽  
Further Education ◽  
Herbicide Application ◽  
Target Movement ◽  
Pesticide Applicator ◽  
Synthetic Auxin ◽  
Survey Results ◽  
Auxin Herbicides ◽  
Pesticide Applicators ◽  
Temperature Inversions

The introduction of soybean and cotton traits with resistance to synthetic auxin herbicides has led to an increase in concern over the off-target movement of dicamba and 2,4-D. A direct-mail survey was sent to Missouri pesticide applicators in January of 2016 to understand current herbicide application practices and applicator knowledge and awareness of the new synthetic auxin technologies. Completed surveys were returned by 2,335 applicators, representing approximately 11% of the state’s registered pesticide applicators. Survey data reported herein provides information regarding current pesticide applicator knowledge and practices and highlights areas that need more emphasis during applicator training. Overall, survey respondents were familiar with physical drift and methods to minimize that risk. However respondents were less familiar with volatility and temperature inversions, which can each influence off-target herbicide movement. Of the 427 commercial applicators and 1,535 noncommercial applicators who answered questions regarding volatility, 81% and 74% respectively, recognized that high temperatures can contribute to a herbicide’s ability to volatilize. However, only 48% and 39% understood that a herbicide’s vapor pressure influences volatility. Answers from the survey indicate further education is needed on the synthetic auxin technologies, such as what herbicides can be used with each technology, proper methods for inspecting and cleaning spray equipment, and the importance of reading herbicide labels. When asked whether applicators were aware of the new 2,4-D-resistant and dicamba-resistant traits, 76% of 443 commercial applicators and only 40% of 1,713 noncommercial applicators selected “yes.” Additionally, survey results suggests that current methods aimed to facilitate communication among producers and applicators, such as FieldWatch and Flag the Technology, may not be successfully adopted, at least in Missouri. Findings from this survey can be utilized to enhance training of pesticide applicators in preparation for the synthetic auxin herbicide technologies.

scholarly journals Inversion Climatology in High-Production Agricultural Regions of Missouri and Implications for Pesticide Applications

2019 ◽  
Vol 58 (9) ◽  
pp. 1973-1992 ◽  
Author(s):  
Mandy D. Bish ◽  
Patrick E. Guinan ◽  
Kevin W. Bradley
Keyword(s):  
Ground Level ◽  
The United States ◽  
Genetically Engineered ◽  
Time Inversion ◽  
Target Movement ◽  
Growing Seasons ◽  
Pesticide Applicators ◽  
Temperature Inversions ◽  
Patterns Of Injury ◽  
Agricultural Regions

ABSTRACTMost pesticides applied in the United States have labels that include language prohibiting application during temperature inversions. This restriction, which is well known and is followed by aerial pesticide applicators, has more recently become a focus for ground pesticide applicators. This is partially due to the recent introduction of genetically engineered soybean and cotton with tolerance to dicamba herbicide. Dicamba has been utilized for more than 50 years to control weeds in grain crops, such as corn. In 2017, dicamba was approved for use in dicamba-tolerant soybean and cotton. In 2017 and 2018, dicamba movement onto nontarget plants was substantial. As based on patterns of injury to nontolerant crops and time of applications, some of which occurred during the evening, inversions were likely contributors to off-target movement. Historically, most research on surface temperature inversions and pesticides focused on aerial applications. Research presented here focused on development of inversion profiles at atmospheric heights relevant to ground applications, which typically occur 46–107 cm above ground level (AGL). During the 2015–17 soybean growing seasons, data were collected at three heights AGL (46, 168, and 305 cm) in three soybean-producing regions of Missouri to characterize inversions. Over 600 inversions were characterized; all were nocturnal in nature. Inversions typically lasted overnight at two locations; duration varied at the third. The largest temperature difference recorded was 6°C. This research has resulted in real-time inversion monitoring that is available online to applicators (http://agebb.missouri.edu/weather/realTime/maps/index.php#temp_inversion), and the data generated can be utilized to improve accuracy of low-level inversion forecasting models.

scholarly journals Off-target Pesticide Movement: A Review of our Current Understanding of Drift Due to Inversions and Secondary Movement

2020 ◽  
pp. 1-43
Author(s):  
Mandy Bish ◽  
Eric Oseland ◽  
Kevin Bradley
Keyword(s):  
Environmental Factors ◽  
Current Understanding ◽  
Target Movement ◽  
Herbicide Resistant ◽  
Pesticide Drift ◽  
Temperature Inversions ◽  
Radiation Cooling ◽  
Light Gaps ◽  
Review Current

Abstract Pesticide drift has been a concern since the introduction of pesticides. Historical incidences with off-target movement of 2,4-D and dichlorodiphenyltrichloroethane (DDT) increased our understanding of pesticide fate in the atmosphere related to aerial pesticide applications. More recent incidences with dicamba have brought to light gaps in our current understanding of aerial pesticide movement following ground pesticide applications. In this paper, we review current understanding of inversions and other weather and environmental factors that contribute to secondary pesticide movement and highlight questions that need to be addressed. Factors that influence volatility and terminology associated with the atmosphere, such as cool air drainage, temperature inversions, and radiation cooling will be discussed. We also present literature that highlights the need to consider the role(s) of wind in secondary drift in addition to the role in physical drift. With increased awareness of pesticide movement and more herbicide-resistant traits available than ever before, it has become even more essential that we understand secondary movement of pesticides, recognize our gaps in understanding, and advance from what is currently unknown.

scholarly journals Characteristics of low-level temperature inversions over the Arctic Ocean during the CHINARE 2018 campaign in summer

2021 ◽  
pp. 118537
Author(s):  
Lei Zhang ◽  
Jian Li ◽  
Minghu Ding ◽  
Jianping Guo ◽  
Lingen Bian ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
The Arctic ◽  
Low Level ◽  
The Arctic Ocean ◽  
Temperature Inversions

scholarly journals Traffic Density-Related Black Carbon Distribution: Impact of Wind in a Basin Town

2021 ◽  
Vol 18 (12) ◽  
pp. 6490
Author(s):  
Borut Jereb ◽  
Brigita Gajšek ◽  
Gregor Šipek ◽  
Špela Kovše ◽  
Matevz Obrecht
Keyword(s):  
Black Carbon ◽  
Carbon Concentration ◽  
Ground Level ◽  
Traffic Density ◽  
Carbon Distribution ◽  
Wind Speeds ◽  
Black Carbon Concentration ◽  
Low Wind Speeds ◽  
Temperature Inversions ◽  
Carbon Concentrations

Black carbon is one of the riskiest particle matter pollutants that is harmful to human health. Although it has been increasingly investigated, factors that depend on black carbon distribution and concentration are still insufficiently researched. Variables, such as traffic density, wind speeds, and ground levels can lead to substantial variations of black carbon concentrations and potential exposure, which is even riskier for people living in less-airy sites. Therefore, this paper “fills the gaps” by studying black carbon distribution variations, concentrations, and oscillations, with special emphasis on traffic density and road segments, at multiple locations, in a small city located in a basin, with frequent temperature inversions and infrequent low wind speeds. As wind speed has a significant impact on black carbon concentration trends, it is critical to present how low wind speeds influence black carbon dispersion in a basin city, and how black carbon is dependent on traffic density. Our results revealed that when the wind reached speeds of 1 ms−1, black carbon concentrations actually increased. In lengthy wind periods, when wind speeds reached 2 or 3 ms−1, black carbon concentrations decreased during rush hour and in the time of severe winter biomass burning. By observing the results, it could be concluded that black carbon persists longer in higher altitudes than near ground level. Black carbon concentration oscillations were also seen as more pronounced on main roads with higher traffic density. The more the traffic decreases and becomes steady, the more black carbon concentrations oscillate.

Non-cooperative maritime target position and velocity measuring method based on monocular trajectory intersection for video satellite

2017 ◽  
Vol 233 (1) ◽  
pp. 44-56 ◽  
Author(s):  
Shengyi Chen ◽  
Haibo Liu ◽  
Xiaochun Liu ◽  
Qifeng Yu
Keyword(s):  
Target Position ◽  
Measuring Method ◽  
Observation Time ◽  
Measuring Error ◽  
Target Movement ◽  
Practical Applications ◽  
High Measurement ◽  
Velocity Measuring ◽  
Elevation Model ◽  
Intersection Method

This paper presents a passive measuring method based on monocular trajectory intersection, aimed at realizing the position and velocity measurement of a non-cooperative maritime target for video satellite. Due to the fact that the target’s moving range is relatively small in comparison to that of the satellite during the observation time, a large measuring error results when directly using the monocular trajectory intersection method for 3D motion measurement. Therefore, the dynamic sea surface elevation model is employed to increase the maritime target movement constraints, which simplifies the 3D spatial motion of the target to 2D surface motion. By combining the surface constraint and monocular trajectory intersection method, measurement robustness for a non-cooperative maritime target can be greatly improved. Furthermore, a line-surface intersection method is proposed to obtain the initial solution for motion parameters, which increases the nonlinear optimization efficiency. Simulation experiments are conducted to analyze the effect of different error factors on position and velocity accuracy. The results indicate that the proposed method achieves high measurement accuracy and is feasible in practical applications for video satellite.

Sign in / Sign up

Export Citation Format

Share Document