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Monty E Myers - One of the best experts on this subject based on the ideXlab platform.
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soil application of sar inducers imidacloprid thiamethoxam and acibenzolar s methyl for citrus canker control in young grapefruit trees
Plant Disease, 2011Co-Authors: J H Graham, Monty E MyersAbstract:Abstract Soil applications of inducers of systemic acquired resistance (SAR) imidacloprid, thiamethoxam, or acibenzolar-S-methyl, at various rates and application frequencies, were evaluated for control of citrus canker caused by Xanthomonas citri subsp. citri in a field trial of 3- and 4-year-old ‘Ray Ruby’ grapefruit trees in southeastern Florida. Reduction of foliar incidence of canker produced by one, two, or four soil applications of imidacloprid, thiamethoxam, and acibenzolar-S-methyl was compared with 11 foliar sprays of copper hydroxide and streptomycin applied at 21-day intervals. In the 2008 and 2009 crop seasons, canker incidence on each set of vegetative flushes was assessed as the percentage of the total leaves with lesions. By the end of the 2008 season, despite above-average rainfall and a Tropical Storm event, all treatments significantly reduced foliar incidence of citrus canker on the combined spring-summer-fall flushes. Sprays of copper hydroxide and streptomycin were effective for redu...
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soil application of sar inducers imidacloprid thiamethoxam and acibenzolar s methyl for citrus canker control in young grapefruit trees
Plant Disease, 2011Co-Authors: J H Graham, Monty E MyersAbstract:Soil applications of inducers of systemic acquired resistance (SAR) imidacloprid, thiamethoxam, or acibenzolar-S-methyl, at various rates and application frequencies, were evaluated for control of citrus canker caused by Xanthomonas citri subsp. citri in a field trial of 3- and 4-year-old 'Ray Ruby' grapefruit trees in southeastern Florida. Reduction of foliar incidence of canker produced by one, two, or four soil applications of imidacloprid, thiamethoxam, and acibenzolar-S-methyl was compared with 11 foliar sprays of copper hydroxide and streptomycin applied at 21-day intervals. In the 2008 and 2009 crop seasons, canker incidence on each set of vegetative flushes was assessed as the percentage of the total leaves with lesions. By the end of the 2008 season, despite above-average rainfall and a Tropical Storm event, all treatments significantly reduced foliar incidence of citrus canker on the combined spring-summer-fall flushes. Sprays of copper hydroxide and streptomycin were effective for reducing canker incidence on shoot flushes produced throughout the season compared with the untreated control, whereas soil-applied SAR inducers reduced foliar disease depending on rate, frequency, and timing of application. Except for the treatment of four applications of acibenzolar-S-methyl at 0.2 g a.i. per tree or two applications of imidacloprid, SAR inducers were ineffective for reducing foliar disease on the flushes that were present during the Tropical Storm. In 2009, all treatments significantly reduced the incidence of foliar canker on the combined spring-summer-fall flushes but not all treatments of spring-summer flushes with SAR inducers were effective compared with the untreated control. Hence, depending on rate, frequency, and timing of application, soil-applied SAR inducers reduced incidence of canker on foliar flushes of young grapefruit trees under epidemic conditions.
Lance F Bosart - One of the best experts on this subject based on the ideXlab platform.
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heavy precipitation associated with southern appalachian cold air damming and carolina coastal frontogenesis in advance of weak landfalling Tropical Storm marco 1990
Monthly Weather Review, 2009Co-Authors: Alan F Srock, Lance F BosartAbstract:Abstract An analysis is presented of Tropical Storm Marco (1990), a Storm that dropped copious amounts of rain over the southeast United States. Marco was noteworthy because of its role in the formation and evolution of two distinct episodes of cold-air damming and coastal frontogenesis over Georgia and the Carolinas. These mesoscale features led to greater than 300 mm of precipitation in 2 days over the near-coastal southeast United States; much of the rain occurred while Marco was over 400 km away. This case is further complicated by two other nearby Tropical cyclones, which affected Marco’s track and the overall rainfall distribution. Synoptic and mesoscale analyses of the development of the coastal front and cold-air damming episodes show that the location of Marco helped to orient low-level winds toward the Appalachians. As rain developed inland, a pocket of relatively cool air, the “cool pool,” formed near the mountain slopes and was partially blocked by the higher terrain. Low-level analyses show t...
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observational analysis of heavy rainfall mechanisms associated with severe Tropical Storm bilis 2006 after its landfall
Monthly Weather Review, 2009Co-Authors: Shuanzhu Gao, Zhiyong Meng, Fuqing Zhang, Lance F BosartAbstract:Abstract This observational study attempts to determine factors responsible for the distribution of precipitation over large areas of southern China induced by Bilis, a western North Pacific Ocean severe Tropical Storm that made landfall on the southeastern coast of mainland China on 14 July 2006 with a remnant circulation that persisted over land until after 17 July 2006. The heavy rainfalls associated with Bilis during and after its landfall can be divided into three stages. The first stage of the rainfall, which occurred in Fujian and Zhejiang Provinces, could be directly induced by the inner-core Storm circulation during its landfall. The third stage of rainfall, which occurred along the coastal areas of Guangdong and Fujian Provinces, likely resulted from the interaction between Bilis and the South China Sea monsoon enhanced by topographical lifting along the coast. The second stage of the rainfall, which appeared inland around the border regions between Jiangxi, Hunan, and Guangdong Provinces, cause...
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postlandfall Tropical cyclone reintensification in a weakly baroclinic environment a case study of hurricane david september 1979
Monthly Weather Review, 1995Co-Authors: Lance F Bosart, Gary M LackmannAbstract:Abstract An analysis is conducted from a potential vorticity (PV) perspective of the reintensification of Tropical Storm David over the northeastern United States in September 1979. David, a major long-lived hurricane, originated near the Cape Verde Islands in late August 1979. It made final landfall in Georgia on 4 September 1979 and weakened rapidly thereafter. The noteworthy aspect of David was its subsequent reintensification approximately 27 h after landfall as a warm-core disturbance in a weakly baroclinic environment. In this regard the redevelopment of David is unlike the classical extraTropical transformation of a Tropical Storm in a strongly baroclinic environment that has been documented in the literature. The authors' analysis of the evolution of the dynamical tropopause subsequent to Storm landfall revealed that David reintensified in response to “tropopause lifting” (upward displacement of the dynamic tropopause) ahead of a nondeepening and otherwise very weak upper-tropospheric disturbance....
J H Graham - One of the best experts on this subject based on the ideXlab platform.
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soil application of sar inducers imidacloprid thiamethoxam and acibenzolar s methyl for citrus canker control in young grapefruit trees
Plant Disease, 2011Co-Authors: J H Graham, Monty E MyersAbstract:Abstract Soil applications of inducers of systemic acquired resistance (SAR) imidacloprid, thiamethoxam, or acibenzolar-S-methyl, at various rates and application frequencies, were evaluated for control of citrus canker caused by Xanthomonas citri subsp. citri in a field trial of 3- and 4-year-old ‘Ray Ruby’ grapefruit trees in southeastern Florida. Reduction of foliar incidence of canker produced by one, two, or four soil applications of imidacloprid, thiamethoxam, and acibenzolar-S-methyl was compared with 11 foliar sprays of copper hydroxide and streptomycin applied at 21-day intervals. In the 2008 and 2009 crop seasons, canker incidence on each set of vegetative flushes was assessed as the percentage of the total leaves with lesions. By the end of the 2008 season, despite above-average rainfall and a Tropical Storm event, all treatments significantly reduced foliar incidence of citrus canker on the combined spring-summer-fall flushes. Sprays of copper hydroxide and streptomycin were effective for redu...
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soil application of sar inducers imidacloprid thiamethoxam and acibenzolar s methyl for citrus canker control in young grapefruit trees
Plant Disease, 2011Co-Authors: J H Graham, Monty E MyersAbstract:Soil applications of inducers of systemic acquired resistance (SAR) imidacloprid, thiamethoxam, or acibenzolar-S-methyl, at various rates and application frequencies, were evaluated for control of citrus canker caused by Xanthomonas citri subsp. citri in a field trial of 3- and 4-year-old 'Ray Ruby' grapefruit trees in southeastern Florida. Reduction of foliar incidence of canker produced by one, two, or four soil applications of imidacloprid, thiamethoxam, and acibenzolar-S-methyl was compared with 11 foliar sprays of copper hydroxide and streptomycin applied at 21-day intervals. In the 2008 and 2009 crop seasons, canker incidence on each set of vegetative flushes was assessed as the percentage of the total leaves with lesions. By the end of the 2008 season, despite above-average rainfall and a Tropical Storm event, all treatments significantly reduced foliar incidence of citrus canker on the combined spring-summer-fall flushes. Sprays of copper hydroxide and streptomycin were effective for reducing canker incidence on shoot flushes produced throughout the season compared with the untreated control, whereas soil-applied SAR inducers reduced foliar disease depending on rate, frequency, and timing of application. Except for the treatment of four applications of acibenzolar-S-methyl at 0.2 g a.i. per tree or two applications of imidacloprid, SAR inducers were ineffective for reducing foliar disease on the flushes that were present during the Tropical Storm. In 2009, all treatments significantly reduced the incidence of foliar canker on the combined spring-summer-fall flushes but not all treatments of spring-summer flushes with SAR inducers were effective compared with the untreated control. Hence, depending on rate, frequency, and timing of application, soil-applied SAR inducers reduced incidence of canker on foliar flushes of young grapefruit trees under epidemic conditions.
Gabriele Villarini - One of the best experts on this subject based on the ideXlab platform.
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dynamical downscaling projections of twenty first century atlantic hurricane activity cmip3 and cmip5 model based scenarios
Journal of Climate, 2013Co-Authors: Thomas R Knutson, Joseph J Sirutis, Stephen T Garner, Isaac M Held, Robert E Tuleya, Gabriel A Vecchi, Ming Zhao, Hyeongseog Kim, Morris A Bender, Gabriele VillariniAbstract:AbstractTwenty-first-century projections of Atlantic climate change are downscaled to explore the robustness of potential changes in hurricane activity. Multimodel ensembles using the phase 3 of the Coupled Model Intercomparison Project (CMIP3)/Special Report on Emissions Scenarios A1B (SRES A1B; late-twenty-first century) and phase 5 of the Coupled Model Intercomparison Project (CMIP5)/representative concentration pathway 4.5 (RCP4.5; early- and late-twenty-first century) scenarios are examined. Ten individual CMIP3 models are downscaled to assess the spread of results among the CMIP3 (but not the CMIP5) models. Downscaling simulations are compared for 18-km grid regional and 50-km grid global models. Storm cases from the regional model are further downscaled into the Geophysical Fluid Dynamics Laboratory (GFDL) hurricane model (9-km inner grid spacing, with ocean coupling) to simulate intense hurricanes at a finer resolution.A significant reduction in Tropical Storm frequency is projected for the CMIP3 ...
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north atlantic Tropical Storm frequency response to anthropogenic forcing projections and sources of uncertainty
Journal of Climate, 2011Co-Authors: Gabriele Villarini, Thomas R Knutson, Gabriel A Vecchi, Ming Zhao, James A SmithAbstract:The impact of future anthropogenic forcing on the frequency of Tropical Storms in the North Atlantic basin hasbeenthesubjectofintensiveinvestigation.However,whetherthenumberofNorthAtlanticTropicalStorms will increase or decrease in a warmer climate is still heavily debated and a consensus has yet to be reached. To shed light on this issue, the authors use a recently developed statistical model, in which the frequency of North Atlantic Tropical Storms is modeled by a conditional Poisson distribution with rate of occurrence parameter that is a function of Tropical Atlantic and mean Tropical sea surface temperatures (SSTs). It is shown how the disagreementamongdynamicalmodeling projectionsoflate-twenty-first-centuryTropicalStorm frequencycan be largely explained by differences in large-scale SST patterns from the different climate model projections used in these studies. The results do not support the notion of large (;200%) increases in Tropical Storm frequency in the North Atlantic basin over the twenty-first century in response to increasing greenhouse gases (GHGs). Because the statistical model is computationally inexpensive, it is used to examine the impact of different climate models andclimate change scenarios on the frequency of North Atlantic Tropical Storms. The authors estimate that the dominant drivers of uncertainty in projections of Tropical Storm frequency over the twenty-first century are internal climate variations and systematic intermodel differences in the response of SST patterns to increasing GHGs. Relative to them, uncertainties in total GHG emissions or other climate forcings, within the scenarios explored here, represent a minor source of uncertainty in Tropical Storm frequency projections. These results suggest that reducing uncertainty in future projections of North Atlantic Tropical Storm frequency may depend as critically on reducing the uncertainty in the sensitivity of Tropical Atlantic warming relative to the Tropical mean, in response to GHG increase, as on improving dynamical or statistical downscaling techniques. Moreover, the large uncertainties on century-scale trends that are due to internal climate variability are likely to remain irreducible for the foreseeable future. As a further illustration of the statistical model’s utility, the authors model projected changes in U.S. landfalling Tropical Storm activity under a variety of different climate change scenarios and climate models. These results are similar to those for the overall number of North Atlantic Tropical Storms, and do not point to a large increase in U.S. landfalling Tropical Storms over the twenty-first century in response to increasing GHGs.
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modeling the dependence of Tropical Storm counts in the north atlantic basin on climate indices
Monthly Weather Review, 2010Co-Authors: Gabriele Villarini, Gabriel A Vecchi, James A SmithAbstract:Abstract The authors analyze and model time series of annual counts of Tropical Storms lasting more than 2 days in the North Atlantic basin and U.S. landfalling Tropical Storms over the period 1878–2008 in relation to different climate indices. The climate indices considered are the Tropical Atlantic sea surface temperature (SST), Tropical mean SST, the North Atlantic Oscillation (NAO), and the Southern Oscillation index (SOI). Given the uncertainties associated with a possible Tropical Storm undercount in the presatellite era, two different time series of counts for the North Atlantic basin are employed: one is the original (uncorrected) Tropical Storm record maintained by the National Hurricane Center and the other one is with a correction for the estimated undercount associated with a changing observation network. Two different SST time series are considered: the Met Office’s HadISSTv1 and NOAA’s Extended Reconstructed SST. Given the nature of the data (counts), a Poisson regression model is adopted. T...
Gabriel A Vecchi - One of the best experts on this subject based on the ideXlab platform.
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the north atlantic oscillation as a driver of rapid climate change in the northern hemisphere
Nature Geoscience, 2016Co-Authors: Thomas L Delworth, Fanrong Zeng, Gabriel A Vecchi, Xiaosong Yang, Liping Zhang, Rong ZhangAbstract:The North Atlantic Oscillation has varied markedly on multidecadal timescales. Analyses of climate simulations show that these variations have contributed to Arctic sea ice loss, Northern Hemisphere warming and Tropical Storm activity.
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dynamical downscaling projections of twenty first century atlantic hurricane activity cmip3 and cmip5 model based scenarios
Journal of Climate, 2013Co-Authors: Thomas R Knutson, Joseph J Sirutis, Stephen T Garner, Isaac M Held, Robert E Tuleya, Gabriel A Vecchi, Ming Zhao, Hyeongseog Kim, Morris A Bender, Gabriele VillariniAbstract:AbstractTwenty-first-century projections of Atlantic climate change are downscaled to explore the robustness of potential changes in hurricane activity. Multimodel ensembles using the phase 3 of the Coupled Model Intercomparison Project (CMIP3)/Special Report on Emissions Scenarios A1B (SRES A1B; late-twenty-first century) and phase 5 of the Coupled Model Intercomparison Project (CMIP5)/representative concentration pathway 4.5 (RCP4.5; early- and late-twenty-first century) scenarios are examined. Ten individual CMIP3 models are downscaled to assess the spread of results among the CMIP3 (but not the CMIP5) models. Downscaling simulations are compared for 18-km grid regional and 50-km grid global models. Storm cases from the regional model are further downscaled into the Geophysical Fluid Dynamics Laboratory (GFDL) hurricane model (9-km inner grid spacing, with ocean coupling) to simulate intense hurricanes at a finer resolution.A significant reduction in Tropical Storm frequency is projected for the CMIP3 ...
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north atlantic Tropical Storm frequency response to anthropogenic forcing projections and sources of uncertainty
Journal of Climate, 2011Co-Authors: Gabriele Villarini, Thomas R Knutson, Gabriel A Vecchi, Ming Zhao, James A SmithAbstract:The impact of future anthropogenic forcing on the frequency of Tropical Storms in the North Atlantic basin hasbeenthesubjectofintensiveinvestigation.However,whetherthenumberofNorthAtlanticTropicalStorms will increase or decrease in a warmer climate is still heavily debated and a consensus has yet to be reached. To shed light on this issue, the authors use a recently developed statistical model, in which the frequency of North Atlantic Tropical Storms is modeled by a conditional Poisson distribution with rate of occurrence parameter that is a function of Tropical Atlantic and mean Tropical sea surface temperatures (SSTs). It is shown how the disagreementamongdynamicalmodeling projectionsoflate-twenty-first-centuryTropicalStorm frequencycan be largely explained by differences in large-scale SST patterns from the different climate model projections used in these studies. The results do not support the notion of large (;200%) increases in Tropical Storm frequency in the North Atlantic basin over the twenty-first century in response to increasing greenhouse gases (GHGs). Because the statistical model is computationally inexpensive, it is used to examine the impact of different climate models andclimate change scenarios on the frequency of North Atlantic Tropical Storms. The authors estimate that the dominant drivers of uncertainty in projections of Tropical Storm frequency over the twenty-first century are internal climate variations and systematic intermodel differences in the response of SST patterns to increasing GHGs. Relative to them, uncertainties in total GHG emissions or other climate forcings, within the scenarios explored here, represent a minor source of uncertainty in Tropical Storm frequency projections. These results suggest that reducing uncertainty in future projections of North Atlantic Tropical Storm frequency may depend as critically on reducing the uncertainty in the sensitivity of Tropical Atlantic warming relative to the Tropical mean, in response to GHG increase, as on improving dynamical or statistical downscaling techniques. Moreover, the large uncertainties on century-scale trends that are due to internal climate variability are likely to remain irreducible for the foreseeable future. As a further illustration of the statistical model’s utility, the authors model projected changes in U.S. landfalling Tropical Storm activity under a variety of different climate change scenarios and climate models. These results are similar to those for the overall number of North Atlantic Tropical Storms, and do not point to a large increase in U.S. landfalling Tropical Storms over the twenty-first century in response to increasing GHGs.
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modeling the dependence of Tropical Storm counts in the north atlantic basin on climate indices
Monthly Weather Review, 2010Co-Authors: Gabriele Villarini, Gabriel A Vecchi, James A SmithAbstract:Abstract The authors analyze and model time series of annual counts of Tropical Storms lasting more than 2 days in the North Atlantic basin and U.S. landfalling Tropical Storms over the period 1878–2008 in relation to different climate indices. The climate indices considered are the Tropical Atlantic sea surface temperature (SST), Tropical mean SST, the North Atlantic Oscillation (NAO), and the Southern Oscillation index (SOI). Given the uncertainties associated with a possible Tropical Storm undercount in the presatellite era, two different time series of counts for the North Atlantic basin are employed: one is the original (uncorrected) Tropical Storm record maintained by the National Hurricane Center and the other one is with a correction for the estimated undercount associated with a changing observation network. Two different SST time series are considered: the Met Office’s HadISSTv1 and NOAA’s Extended Reconstructed SST. Given the nature of the data (counts), a Poisson regression model is adopted. T...