Comments on: Accuracy of Raman Lidar Water Vapor Calibration and its Applicability to Long-Term Measurements

In a recent publication, LeBlanc and McDermid proposed a hybrid calibration technique for Raman water vapor lidar involving a tungsten lamp and radiosondes. Measurements made with the lidar telescope viewing the calibration lamp were used to stabilize the lidar calibration determined by comparison with radiosonde. The technique provided a significantly more stable calibration constant than radiosondes used alone. The technique involves the use of a calibration lamp in a fixed position in front of the lidar receiver aperture. We examine this configuration and find that such a configuration likely does not properly sample the full lidar system optical efficiency. While the technique is a useful addition to the use of radiosondes alone for lidar calibration, it is important to understand the scenarios under which it will not provide an accurate quantification of system optical efficiency changes. We offer examples of these scenarios

Obtenção da Altura da Camada Limite Planetária a Partir do Método das Imagens

Este trabalho aborda a identificação da altura da CLP a partir de uma nova técnica intitulada Método das Imagens. Tal método foi empregado a partir de dados do sistema LIDAR, obtidos na campanha do projeto CHUVA-SUL e validado a partir de dados de radiossondagem

Evaluation of the potential for greenhouse gas (CO2 , CH4 ) emissions in the southern São Paulo coastal region, Cananéia-Iguape system

The emissions of CH4 and CO2, the primary greenhouse gases, have a significant impact on radiative forcing.This study investigated these gases along the Cananéia-Iguape estuarine system on the southern coastof the State of São Paulo, Brazil, which is a mangrove region characterized by low anthropogenic impactand a sparse population. As such, this area provides an ideal location for identifying natural emissions andbackground concentrations. The data for this study were collected using a portable gas analyzer (LGRICOSTM GLA131), known for its high sensitivity and precision in detecting gases, mounted on a researchboat. The results obtained were promising for both gases. A small variability in CH4 concentrations wasobserved along the route, ranging from 1.84 ppm to 1.95 ppm, while CO2, showed greater variation invalues obtained during routes, ranging from approximately 411 ppm to 575 ppm. This study underscoresthe importance of investigating areas with minimal environmental impact. Together with future analyses, thisresearch should help improve Greenhouse Gas (GHG) inventories in Brazil by providing valuable baselinedata for comparisons with more impacted areas

Analyzing the atmospheric boundary layer using high-order moments obtained from multiwavelength lidar data: impact of wavelength choice

The lowest region of the troposphere is a turbulent layer known as the atmospheric boundary layer (ABL) and characterized by high daily variability due to the influence of surface forcings. This is the reason why detecting systems with high spatial and temporal resolution, such as lidar, have been widely applied for researching this region. In this paper, we present a comparative analysis on the use of lidar-backscattered signals at three wavelengths (355, 532 and 1064 nm) to study the ABL by investigating the highorder moments, which give us information about the ABL height (derived by the variance method), aerosol layer movement (skewness) and mixing conditions (kurtosis) at several heights. Previous studies have shown that the 1064 nm wavelength, due to the predominance of particle signature in the total backscattered atmospheric signal and practically null presence of molecular signal (which can represent noise in high-order moments), provides an appropriate description of the turbulence field, and thus in this study it was considered a reference. We analyze two case studies that show us that the backscattered signal at 355 nm, even after applying some corrections, has a limited applicability for turbulence studies using the proposed methodology due to the strong contribution of the molecular signature to the total backscatter signal. This increases the noise associated with the high-order profiles and, consequently, generates misinformation. On the other hand, the information on the turbulence field derived from the backscattered signal at 532 nm is similar to that obtained at 1064 nm due to the appropriate attenuation of the noise, generated by molecular component of backscattered signal by the application of the corrections proposedThis research has been supported by the Andalusian Regional Government (P12-RNM-618 2409 project), the Spanish Agencia Estatal de Investigación (AEI, CGL2016-81092- R, CGL2017-90884-REDT and CGL2017-83538-C3-1-R projects), the Spanish Ministry of Economy and Competitiveness (CGL2016- 81092-R, and CGL2017-90884-REDT projects), the European Union’s Horizon 2020 project (NACTRIS 2, grant no. 621654109), the University of Granada, the National Council for Scientific and Technological Development (CNPQ, 152156/2018-6, 432515/2018-6 and 150716/2017-6 projects), the São Paulo Research Foundation (FAPESP, grant no. 2015/12793-0), and the FEDER program for the University of Granada

Identificação da Intrusão da Brisa Marítima sobre a Região Metropolitana de São Paulo através da Técnica Lidar Aliada à Análise Meteorológica

Este trabalho visa estudar a intrusão de ar “limpo”, sobre a regiãometropolitana de São Paulo (RMSP), proveniente do processo de brisamarítima (BM), utilizando a técnica LIDAR aliada à análise meteorológica

The entangling side of the Unruh-Hawking effect

We show that the Unruh effect can create net quantum entanglement between inertial and accelerated observers depending on the choice of the inertial state. This striking result banishes the extended belief that the Unruh effect can only destroy entanglement and furthermore provides a new and unexpected source for finding experimental evidence of the Unruh and Hawking effects.Comment: 4 pages, 4 figures. Added Journal referenc

Evaluation of atmospheric aerosols in the metropolitan area of São Paulo simulated by the regional EURAD-IM model on high-resolution

We present a high-resolution air quality study over São Paulo, Brazil with the EURopean Air Pollution Dispersion - Inverse Model (EURAD-IM) used for the first time over South America simulating detailed features of aerosols. Modeled data are evaluated with observational surface data and a Lidar. Two case studies in 2016 with distinct meteorological conditions and pollution plume features show transport (i) from central South America, associated to biomass burning activities, (ii) from the rural part of the state of São Paulo, (iii) between the metropolitan areas of Rio de Janeiro and São Paulo (MASP) either through the Paraíba Valley or via the ocean, connecting Brazil's two largest cities, (iv) from the port-city Santos to MASP and also from MASP to the city Campinas, and vice versa. A Pearson coefficient of 0.7 was found for PM10 at MASP CENTER and EURAD-IM simulations vary within the observational standard deviation, with a Mean Percentual Error (MPE) of 10%. The model's vertical distributions of aerosol layers agree with the Lidar profiles that show either characteristics of long-range transported biomass burning plumes, or of local pollution. The distinct transport patterns that agree with satellite Aerosol Optical Death and fire spot images as well as with the ground-based observations within the standard deviations, allows us exploring patterns of air pollution in a detailed manner and to understand the complex interactions between local to long-range transport sources.This study was financed in part by the Coordenaç ̃ao de Aperfeiçoamento de Pessoal de Nível Superior - Brazil (CAPES) - Finance Code 001, Brazil, for the doctoral scholarship granted. This article and the research behind it are a direct contribution to the research themes of the Klimapolis Laboratory (klimapolis.net

LALINET: The First Latin American–Born Regional Atmospheric Observational Network

Sustained and coordinated efforts of lidar teams in Latin America at the beginning of the 21st century have built LALINET (Latin American Lidar NETwork), the only observational network in Latin America created by the agreement and commitment of Latin American scientists. They worked with limited funding but an abundance of enthusiasm and commitment toward their joint goal. Before LALINET, there were a few pioneering lidar stations operating in Latin America, described briefly here. Bi-annual Latin American Lidar Workshops, held from 2001 to the present, supported both the development of the regional lidar community and LALINET. At those meetings, lidar researchers from Latin America meet to conduct regular scientific and technical exchanges among themselves and with experts from the rest of the world. Regional and international scientific cooperation has played an important role for the development of both the individual teams and the network. The current LALINET status and activities are described, emphasizing the processes of standardization of the measurements, methodologies, calibration protocols, and retrieval algorithms. Failures and successes achieved in the buildup of LALINET are presented. In addition, the first LALINET joint measurement campaign and a set of aerosol extinction profile measurements obtained from the aerosol plume produced by the Calbuco volcano eruption on April 22, 2015, are described and discussed.Fil: Antuña Marrero, Juan Carlos. Centro Meteorológico de Camagüey; CubaFil: Landulfo, Eduardo. Instituto de Pesquisas Energéticas e Nucleares; BrasilFil: Estevan, René. Centro Meteorológico de Camagüey; CubaFil: Barja, Boris. Centro Meteorológico de Camagüey; Cuba. Universidade de Sao Paulo; BrasilFil: Robock, Alan. State University of New Jersey; Estados UnidosFil: Wolfram, Elian Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Ristori, Pablo Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Clemesha, Barclay. Upper Atmosphere Research Group; BrasilFil: Zaratti, Francesco. Universidad Mayor de San Andrés; BoliviaFil: Forno, Ricardo. Universidad Mayor de San Andrés; BoliviaFil: Armandillo, Errico. ESTEC; Países BajosFil: Bastidas, Álvaro E.. Universidad Nacional de Colombia. Sede Medellin; ColombiaFil: de Frutos Baraja, Ángel Máximo. Universidad de Valladolid; EspañaFil: Whiteman, David N.. National Aeronautics and Space Administration; Estados UnidosFil: Quel, Eduardo Jaime. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Barbosa, Henrique M. J.. Universidade de Sao Paulo; BrasilFil: Lopes, Fabio. Comissao Nacional de Energia Nuclear. Centro de Lasers e Aplicacoes. Instituto de Pesquisas Energeticas e Nucleares.; BrasilFil: Montilla-Rosero, Elena. Universidad de Concepción; Chile. Universidad Escuela de Administración, Finanzas e Instituto Tecnológico; ColombiaFil: Guerrero Rascado, Juan L.. Comissao Nacional de Energia Nuclear. Centro de Lasers e Aplicacoes. Instituto de Pesquisas Energeticas e Nucleares.; Brasil. Universidad de Granada; Españ