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When snow particles fall and pass through the melting layer, they melt from the surface and change into rain particles. At this time, due to the difference in permittivity between ice and water, reflectivity appears large, and this is called the bright band (BB). Since the BB causes confusion in the precipitation estimation of weather radar, many studies on BB detection have been conducted to improve the quantitative precipitation estimation accuracy of weather radar and the performance of numerical models. Wind profiler radar (WPR) is useful for vertical structure analysis of mesoscale convective systems with excellent temporal and vertical spatial resolution. We analyzed the bright band of Typhoon HAISHEN passing near the Korean Peninsula from 00 UTC on September 06 to 00 UTC on September 07, 2020 by 9-site WPR. As the HAISHEN approached, distinct precipitation patterns and BB were detected with vertical signal to noise ratio and vertical radial velocity. The BB height gradually increased as the typhoon approached, and decreased as it moved away. Therefore, the precipitation converged in the front of the typhoon and originated from a stratiform structure. It is known that the BB height depends on local factors such as ground temperature and topography. However, the BB height in Jeju Island and Chupungnyeong, located on the mountain boundary at about 240 m above sea level, showed 3-4 km and 4-5 km, respectively. In order to understand the structure of a rapidly developing precipitation cell, it is necessary to investigate the dynamic parameters which are optimal to retrieve based on WPR.

Representative meteorological instruments that utilize the Doppler effect include Doppler radar, wind profiler, and wind lidar. The latter two instruments produce a vertical profile of winds in high spatio-temporal resolution, in the atmospheric boundary layer. Wind lidar observes with a vertical resolution of 50 m or less and a temporal resolution in minutes, so it fills the observation gap in the lower layer where the wind profiler misses meteorological data. The wind lidar makes the wind vector using DBS (Doppler Beam Swinging) and VAD (Velocity Azimuth Display) methods. It is known that the wind by the VAD method is more accurate than the wind by the DBS method. The DBS method has the advantage of obtaining a wind profile with a fast scan time. On the other hand, there is a restriction that requires at least two beams including vertical beams (one of the east and west beams, and one of the south and north beams), which causes a decrease in the data acquisition rate. The VAD method was improved to produce more wind vector of the wind profiler as well as the wind lidar, which generally uses 5 beams. First, the Fourier series was estimated with the radial velocity by the DBS method. Next, the wind vector was determined by setting the azimuth interval and applying the radial velocity by the Fourier series to the VAD method. The wind vectors were retrieved at the altitude where the wind was not calculated by the DBS method, and the results of the two methods were consistent at the altitude where the wind was calculated by the DBS and the improved VAD method. In this study, we propose a method to increase the data acquisition rate even if the vertical beam or one of the inclined beams is insufficient.

In the atmospheric boundary layer (ABL), the humidity profile was retrieved by combining the data of the radiometer and the wind profiler, and was compared with that of the GPS radiosonde. The variation of the amount of precipitable water (PW) was analyzed in sea breeze, typhoon, and precipitation cases. High-frequency electromagnetic waves emitted from the wind profiler are affected by atmospheric thermodynamic factors (temperature, humidity, and atmospheric pressure). An algorithm was developed to determine the optimal vertical gradient of refractivity (M) which plays important role in the vertical variation of humidity. M was corrected in consideration of the boundary layer height estimated by the wind profiler and the humidity characteristics in the mixed layer. The root mean square error (RMSE) of the retrieved specific humidity was 1.72 g/kg, which was twice as low as the RMSE 3.42 g/kg of radiometer specific humidity. The variation of PW is essential for understanding the structure of the ABL. As the sea breeze blows, the PW increased in the lower layer. As the typhoon approaches the Korean Peninsula, the lower level PW increased rapidly. The PW before and after precipitation showed clear increase and decrease, respectively except for summer season when there is enough water vapor

In this paper, the applicability and usefulness of windprofiler input data were investigated to generate three dimensional wind field. A logical diagnostic model CALMET with windprofiler data at ten sites and with weather forecasting model WRF output was evaluated by statistically comparing with the radiosonde data at eight sites. The horizontal wind speed from CALMET simulated with hourly windprofiler data is in good agreement with radiosonde observations within 1.5 m/s of the root mean square error, especially local circulation of wind such as sea breeze over the coastal region. The root mean square error of wind direction ranged is due to the wind direction error from the windprofiler polluted by ground clutters. Since the exact wind can be produced quickly and accurately in most of the altitude with windprofiler data on CALMET, we expect the method presented in this study to be useful for the monitoring of safe environment as well as weather in the coastal zone.

Wind profiler provides vertical profiles of three-dimensional wind vectors with high spatiotemporal resolution. The wind vectors is useful to analyze severe weather phenomena and to validate the various products from numerical weather prediction model. However, the wind measurements are not immune to ground clutter, bird, insect, and aircraft. Therefore, quality of wind vectors from wind profiler must be quantitatively evaluated prior to its application. In this study, wind vectors from UHF wind profiler at Ganwon Regional Meteorological Administration was quantitatively evaluated using 27 radiosonde measurements that were launched every two or three hours according to rainfall intensity during Intensive Observation Period (IOP) from June to July 2013. In comparison between two measurements, wind vectors from wind profiler was relatively underestimated. In addition, the accuracy and quality of wind vectors from wind profiler decrease with increasing beam height. The accuracy and quality of the wind vectors for rainy periods during IOP were higher than for the clear-air measurements. The moderate rainfall intensity lead to multi-peaks in Doppler spectrum. It results in overestimation of vertical air motion, whereas wind vectors from wind profilers shows good agreement with those from radiosonde measurements for light rainfall intensity.

The momentum flux and the sensible heat flux were measured with the scintillometers and ultrasonic anemometers at 6 sites of which surface characteristics like roughness length and zero-displacement are different each other. We estimated the momentum flux and the sensible heat flux based on the bulk transfer method with the drag coefficient and the heat transfer coefficient calculated from the temperature and wind speed at two heights. The variation of bulk transfer coefficients showed a remarkable difference depending on the atmospheric stability which is less influenced by the zero-displacement than the roughness length. The estimated sensible heat fluxes were in good agreement with those measured at 3 m, showing 23.7 Wm -2 of the root mean square error that is less than 10% of its maximum. Since the estimated momentum flux is not only effected by drag coefficient but also by wind speed square, the determination of wind speed in the bulk transfer method is critical. Key words

The effects of building-roof cooling on flow and air temperature in 3D urban street canyons are numerically investigated using a computational fluid dynamics (CFD) model. The aspect ratios of the building and street canyon considered are unity. For investigating the building-roof cooling effects, the building-roof temperatures are systematically changed. The traditional flow pattern including a portal vortex appears in the spanwise canyon. Compared with the case of the control run, there are minimal differences in flow pattern in the cases in which maximum building-roof cooling is considered. However, as the building roof becomes cooler, the mean kinetic energy increases and the air temperature decreases in the spanwise canyon. Building-roof cooling suppresses the upward and inward motions above the building roof, resultantly increasing the horizontal velocity near the roof level. The increase in wind velocity above the roof level intensifies the secondarily driven vortex circulation as well as the inward (outward) motion into (out of) the spanwise canyon. Finally, building-roof cooling reduces the air temperature in the spanwise canyon, supplying much relatively cool air from the streamwise canyon into the spanwise canyon.

In this study, before and after sunset carbon dioxide concentration and air temperature were observed in two points of atmosphere (lower observation point of the GL + 0.1 m, the upper observation point of GL + 1.0 m) on the foreshore at located in Suncheon Bay and their variations were analyzed. Observation was performed on the foreshore on 2~4 August 2010. Instrument (VAISALA, GMP343) was set two hours before sunset and then observation was made continuously for six hours. In three days, observed carbon dioxide concentration was 375~419 ppm, and the air temperature was in the range of 28.7~32.5 . The average concentration of carbon dioxide was 388~399 ppm in the upper observation point and 386~396 ppm in the lower observation point. It was higher in the upper observation point and its fluctuations were similar in two observation points. Correlation coefficients between carbon dioxide concentration and air temperature in the upper observation point were in the range of 0.64~ 0.88, and were calculated 0.65 to -0.90 in the lower observation point. For the carbon dioxide concentration, correlation coefficients between the upper part and the lower part were very high as 0.98 in three times. For th e air temperature, correlation coefficients between the upper part and the lower part were very high as 0.97 and 0.99. In the sam e observation time, the slope of the linear regression function as carbon dioxide concentration in the lower observation point fo r the upper observation point was in the range of 0.97~1.01. Carbon dioxide concentration Gwas slightly higher in the upper observation point. Because carbon dioxide in the lower observation point was closer on the surface of the foreshore and absorbed from atmosphere to the foreshore. In this study, it was showed that the vertical variation of carbon dioxide concentration was insignificant in the several meter scale of atmosphere on the surface of the foreshore.Key words : Foreshore, Sunset, Carbon dioxide, Air temperature

We simulate and analyze the temporal variation characteristics of PM10, which are particles with an aerodynamic diameter of less than 10 microns, and meteorological factors (temperature, humidity, and wind speed) in eight cities on the Korean peninsula. We employ the detrended cross-correlation analysis (DCCA) method to extract the overall tendency of the hourly variation. The relationships between the PM10 density and meteorological factors are established by using cross-correlation coefficients. As a result of non-Asian dust events, we ascertain from weekly intervals that Andong has the largest value, while Mokpo has the smallest one, in the case of the DCCA cross-correlation coefficient between the PM10 and the temperature. Particularly, the cross-correlations can be compared in eight cities, after we examine whether the cross-correlation would be statistically significant from the random number and the shuffled time series surrogations.

Quantitative precipitation estimation (QPE) is one of the most important elements in meteorological and hydrological applications. In this study, we adjusted the QPE from an S-band weather radar based on co-kriging method using the geostatistical structure function of error distribution of radar rainrate. In order to estimate the accurate quantitative precipitation, the error of radar rainrate which is a primary variable of co-kriging was determined by the difference of rain rates from rain gauge and radar. Also, the gauge rainfield, a secondary variable of co-kriging is derived from the ordinary kriging based on raingauge network. The error distribution of radar rain rate was produced by co-kriging with the derived theoretical variogram determined by experimental variogram. The error of radar rain rate was then applied to the radar estimated precipitation field. Locally heavy rainfall case during 6-7 July 2009 is chosen to verify this study. Correlation between adjusted one-hour radar rainfall accumulation and rain gauge rainfall accumulation improved from 0.55 to 0.84 when compared to prior adjustment of radar error with the adjustment of root mean square error from 7.45 to 3.93 mm.

This research investigated to reduce mass of heavy metals in AMD(acid mine drainage) by microbial mats formed on the channel bed. As, Cd, Cu, Fe, Mn and Zn components were monitored in water and microbial mats, at three points (AMD1, AMD2 and AMD3), in a total of six times. Average daily discharge mass of heavy metals was highest in July, Fe component contained more than 76% of total discharge mass. Discharge mass of heavy metals of AMD and heavy metal contents in microbial mats decreased with downstream at channel. Heavy metal components that average daily discharge mass is over 0.5 kg were Fe, Cu and Zn, and they were highest in July. Average removal efficiency of heavy metals in AMD was highest about 21% in Fe, this microbial mats were due to form from precipitation of Fe component in AMD by aerobic iron bacteria. Relative content for As component in microbial mats than AMD was over 16 times, this As components were due to absorb at iron oxide and iron hydroxide on the surface of microbial mats.

The degradation characteristics of TCE by Ferrate(VI) oxidation have been studied. Ferrate(VI) were prepared by electrochemical method. The degradation efficiency of TCE in aqueous solution was investigated at various pH values, Ferrate(VI) doses and aqueous solution temperature values. GC-ECD was used to analyze TCE. TCE was degraded rapidly by ferrate(VI) in aqueous solution, Also, the experimental results showed that TCE removal efficiency increased with the increase of Ferrate(VI) doses. The effect of pH was investigated and the maximum degradation efficiency was obtained at pH 7. And intermediate products were identified by GC-MS techniques. Ethyl Chloride, Dichloroethylene, Chloroform, 1,1-dichloropropene, Trichloroacetic acid and Trichloroethane were identified as a reaction intermediate, and was identified as an end product.

Usually a single literature-suggested Z-R relationship, where Z the radar reflectivity factor and R the rain rate, is used for weather radar data interpretation. It is desirable to calculate a Z-R relationship by precipitation type to improve the accuracy of quantitative rainfall rate in case of coexistence of different precipitation types, such as, in the area of precipitation produced from a Mesoscale Convective System (MCS). In general, in the MCS trailing anvil, the stratiform precipitation does not fall as drizzle. Rather, the rainfall can assume significant intensity (~10 mm h-1) with showery character. For that reason, in this study, the precipitations were classified into convective and stratiform type, to produce optimum rainfall estimates. Therefore, Z-R relationships were developed for the Eastern Coast of Northeastern Brazil (NEB) using rainfall raindrop size distribution (DSD) data collected with a disdrometer RD-69, aiming their utilization to start the operation of a weather radar system. In this study, due to operation and maintenance facilities, the disdrometer was installed in the Campus of the Universidade Federal de Alagoas (The Federal University of Alagoas) in Maceió in 2001, 12 months before the complete installation of a new radar system. The DSD was stratified by rainfall rate classes. It is found that the DSD are clearly dependent on the parameters of the analytical distribution functions are, and show a marked monthly variability. The parameters of the frequency distributions are dependent on R. The forms of DSDs are similar but the amount of droplets in each one very strongly. This may be possible due to the short period of data collection or to the intraseasonal rainfall variability. The general relationship for the Eastern Coast of NEB was found to be Z = 176.5 R1.29, with correlation coefficient equal to 0.83. This equation is in accordance with the ones for stratiform rain reported in the literature. We found that the convective rain observed is produced by convective cells imbedded into stratiform cloud layers. However, when separating stratiform and convective rainfall we found that the linear coefficient of the Z-R relation is significantly smaller for convective rainfall than for stratiform one (65 and 167 respectively), but the exponential coefficient is higher for convective than for stratiform (1.69 and 1.26 respectively). A relação Z-R, onde Z é o fator reflectividade radar e R a taxa de chuva, utilizada para interpretação de dados de radar meteorológico é geralmente baseada nas relações sugeridas na literatura. É importante calcular uma relação Z-R para diferentes regimes de precipitação para a melhoria da exatidão dos quantitativos de taxa de chuva, principalmente em caso de coexistência de diferentes tipos de precipitação, como por exemplo, na área de precipitação produzida a partir de um Sistema Convectivo de Meso-escala (MCS). Em geral, no MCS, acoplados à bigorna, a precipitação estratiforme pode não ocorrer como chuvisco. Ao contrário, a precipitação pode assumir uma intensidade maior (~10 mm h-1) e, com características claramente flutuantes, apresentar pancadas de chuva. Por essa razão, neste estudo, as precipitações foram classificadas como convectivas e estratiformes, para se obter melhores estimativas de chuva. Portanto, relações Z-R foram estabelecidas para a Costa Leste do Nordeste do Brasil (NEB) utilizando dados de precipitação obtidos com um Disdrômetro RD-69, visando a operação de um novo sistema de radar meteorológico. Neste estudo, devido às facilidades de operação, manutenção e instalações, o Disdrômetro foi instalado no campus da Universidade Federal de Alagoas em Maceió em 2001, 12 meses antes de completar a instalação do sistema de radar. A Distribuição do tamanho de gotas (DSD) foi estratificada por classes de taxa chuvas. Verificou-se que as DSDs dependem claramente dos parâmetros das funções de distribuição analíticas e mostram uma variabilidade mensal acentuada. Os parâmetros da freqüência de distribuição são dependentes de R. As formas das DSDs são similares, mas a quantidade de gotas em cada uma varia consideravelmente. Isto possivelmente pode ser devido ao curto período de coleta de dados ou devido à variabilidade intra-sazonal. A relação Z-R geral para a Costa Leste do NEB é Z = 176,5 R1.29, com coeficiente de um correlação de 0,83. Esta equação está em conformidade com as equações encontradas para chuvas estratiformes descritas na literatura. Constata-se que as chuvas convectivas observadas são produzidas por células convectivas normalmente embutidas em camadas de nuvens estratiformes. No entanto, quando se separa chuvas estratiformes das convectivas, verifica-se que o coeficiente linear da relação Z-R é significativamente menor para chuvas convectivas do que para as estratiformes (65 e 167 respectivamente), mas, o coeficiente exponencial é maior para as convectivas do que para as chuvas estratiformes (1,69 e 1,26 respectivamente).

The SEMAPHORE (Structure des Echanges Mer-Atmosphere, Proprietes Oceaniques/ Recherche Experimentale) experiment, which took place between 04 Oct. and 17 Nov. 1993, was conducted over the oceanic Azores current located in the Azores basin. The SST (Sea Surface Temperature) field was characterized in the SEMAPHORE area (31°–38°N; 21°–28°W) by a large meander with a SST gradient of about 1°C per 100 km. In order to study the evolution of the MABL (Marine Atmospheric Boundary Layer) over the ocean, the mean and the turbulent data were evaluated by the measurement with two aircraft and a ship in different meteorological conditions. Three cases of low pressure and three cases of high pressure are mainly presented here. For the six cases, the satellite images (NOAA) did not show any relation between the SST field and the cloud cover. At each flight level, the decrease of the SST with the altitude due to the divergence of the infrared radiation flux from the ocean is 0.25°C per 100 m. For the comparison between the two aircraft, the mean thermodynamic and dynamic parameters show a good agreement except for the temperature. The dispersion of the sensible heat flux is larger than that of the latent heat flux due to the weak sensible heat flux over the ocean both in the intercomparison between two aircraft and in the comparison between the aircraft and the ship.

Actual evapotranspiration (AET) in the Suyeong-gu was estimated and correlations between AET and meteorological factors were analyzed. The study area was Suyeong-gu lay at the east longitude 05' 40" ~ 129 08' 08" and north latitude 07' 59" ~ 11' 01". The Kumryun mountain, the Bae mountain, the Suyeong river and the Suyeong bay are located on west, north, northeaster and south side in the study area, respectively. AET was estimated using precipitation (P), potential evapotranspiration (PET) and plant-available water coefficient. Meteorological factors to estimate PET were air temperature, dewpoint temperature, atmospheric pressure, duration of sunshine and mean wind speed (MWS). PET and AET were estimated by a method of Allen et al. (1998) and Zhang et al. (2001), respectively. PET was the highest value (564.45 mm/yr) in 2002 year, while it was the lowest value (449.95 mm/yr) in 2003 year. AET was estimated highest value (554.14 mm/yr) in 2002 year and lowest value (427.91 mm/yr) in 2003 year. Variations of PET and AET were similar. The linear regression function of AET as PET using monthly data was AET=0.87PET+3.52 and coefficient of determination was high, 0.75. In order to analyze relationship between the evapotranspiration and meteorological factors, correlation analysis using monthly data were accomplished. Correlation coefficient of AET-PET was 0.96 high, but they of AET-P and PET-P were very low. Correlation coefficients of AET-MWS and PET-MWS were 0.67 and 0.73, respectively. Thus, correlation between evapotranspiration and MWS was the highest among meteorological factors in Suyong-gu. This means that meteorological factor to powerfully effect for the variation of evapotranspiration was MWS. The linear regression function of AET as MWS was AET=84.73MWS+223.05 and coefficient of determination was 0.54. The linear regression function of PET as MWS was PET=83.83MWS+203.62 and coefficient of determination was 0.45.

This paper was studied respiration rate with physicochemical properties of soils at wetland, paddy field and forest in Nongju-ri, Haeryong-myeon, Suncheon city, Jeollanam-do. Soil temperature and respiration rate were measured at the field, and soil pH, moisture and soil organic carbon were analyzed in laboratory. Field monitoring was conducted at 6 points (W3, W7, W13, W17, W23, W27) for wetland, 3 points (P1, P2, P3) for paddy field and 3 points (F1, F2, F3) for forest in 10 January 2009. concentrations in chamber were measured 352~382 ppm for wetland, 364~382 ppm for paddy field and 379~390 ppm for forest, and the average values were 370 ppm, 370 ppm and 385 ppm, respectively. respiration rates of soils were measured for wetland, for paddy field and for forest, and the average values were , and . was uptake from air to soil in wetland and paddy field, but it was emission from soil to air in forest. respiration rate function in uptake condition increased exponential and linear as soil temperature and soil organic carbon. But, it in emission condition decreased linear as soil temperature and soil organic carbon. respiration rate function in wetland decreased linear as soil moisture, but its in paddy and forest increased linear as soil moisture. respiration rate function in all sites increased linear as soil pH, and increasing rate at forest was highest.

Hydraulic gradient of the landfill soils is estimated by Devlin (2003) method, and its variation characteristics from rainfall and permeability of the aquifer material are analyzed. The study site of 18 m 12 m is located in front of the Environment Research Center at the Pukyong National University, and core logging, slug/bail test and groundwater monitoring was performed. The sluglbail tests were performed in 9 wells (except BH9 well), and drawdown data with elapsed time for bail tests were analyzed using Bouwer-Rice and Hvorslev methods. The average hydraulic conductivity estimated in each of the test wells was ranged , and the average hydraulic conductivity in the study site was estimated for arithmetic average, for geometric average and for harmonic average. The permeability of landfill soils was higher at the east side of the study site than at the west side. Groundwater level in 10 wells was monitored 44 times from October 2 to November 7, 2007. The groundwater level was ranged 1.1871.610 m, and the average groundwater level range in each of the well showed 1.2561.407 m. The groundwater level was higher at the east side than at the west side of the study site, and this distribution is identify to it of hydraulic conductivity. The hydraulie gradient and the major flow direction for 10 wells were estimated 0.00720.0093 and , respectively. Also, the hydraulic gradient and the major flow direction for 9 wells were estimated 0.01020.0124 and , respectively. The hydraulic gradient of the study site increased from rainfall (83.5 mm) on October 7, causing by that the groundwater level of the site with high permeability was higher. The hydraulic gradient estimated on and after October 16 was stable, due to almost no rainfall. Thus, it was confirmed that the variation of the hydraulic gradient in the landfill soils was controlled by the rainfall.

1,4-Dioxane is an EPA priority pollutant found in contaminated groundwater and industrial effluents. The common treatment techniques are not effective for 1,4-dioxane degradation. Thus there is a need to find an efficient degradation method such as a photo-Fenton process and understand the degradation mechanism of 1,4-dioxane during such reactions. In this study, the effect of the reaction parameters such as initial concentration of 1,4-dioxane, H2O2 and FeSO4 dosages, and UV light intensity on 1,4-dioxane degradation has been examined. Under optimal conditions, over 95% of 1,4-dioxane is degraded by photo-Fenton (UV with H2O2 and FeSO4), while little 1,4-dioxane is degraded by FeSO4 alone. It was proposed that 1,4-dioxane was oxidized by OH radicals and sequentially led to formation of malonic acid, formic acid and acrylic acid. Based on the experimental results of 1,4-dioxane, the application of advanced oxidation processes (AOPs) appears to be a promising alternative for 1,4-dioxane removal in various environment systems.

The photodegradation of a specific organic pollutant using the Fenton and the photo-Fenton processes has been examined in aqueous solution. The applications of the Fenton process and the photo-Fenton process to the degradation of 2-chlorophenol (2-CP) were investigated. The dependence on the following experimental conditions had been evaluated: initial pH (1.0-9.0), hydrogen peroxide (0.67-2 mM), ferrous ions (0.1-2 mM), initial concentra- tion of 2-CP (0.1-2 mM). The optimal experimental conditions were 1 mM H2O2, 1 mM ferrous ion and pH 3.0. Under the optimal conditions, the degradation efficiency of 2-CP in the photo-Fenton process was enhanced 4% more than that of the Fenton process. Experimental results about the degradation of 2-CP show that UV irradiation improves the degradation efficiency of the Fenton process. The major intermediate formed during the degradation of 2-CP was p- benzoquinone.

Através dos dados de superfície, radiossondagem e radar Doppler banda - L, em Serpong - Indonésia (6° 24’ S - 106° 42’ E), durante a estação seca (1993) e chuvosa (1994) foram estudadas as características da CLAT. Os dados de radar foram validados através da radiossondagem por métodos estatísticos (índice de correlação, média e desvio padrão). A estrutura da CLAT foi interpretada através do eco de radar (vento), observado continuamente para todos os dias do período de estudo. As características mais evidentes da CLAT nesta região foram à presença de uma CM (Camada de Mistura) diurna que atingia a 0,3 km pela manhã e outra camada entre 3-5 km à tarde, observando-se um ciclo diurno de crescimento e estacionariedade, devido ao aquecimento e resfriamento da superfície. A principal característica entre as estações foi que no horário de 0300 TL (Tempo Local), ambas apresentavam o mesmo comportamento (intensidade e direção do vento), mas para o restante do dia existiu uma grande diferença entre elas. Na estação seca a intensidade e a direção do vento foi mais variável do que na chuvosa, resultado observado na altura da CLAT. As informações obtidas através do BLR (Boundary Layer Radar), mostram a existência de pronunciadas variações diurnas na CLAT em dias claros. Verificou-se que a variação diurna da CLAT teve uma influencia marcante, devido à existência da circulação de brisa marítima, confirmada pelo BLR no dia 12/10/93. A validação dos dados do radar apresentou resultados significativos, onde na estação seca, os coeficientes de regressão variaram entre 0,83 e 0,94, tanto na direção como na intensidade, e na chuvosa variou de 0,77 a 0,88 (intensidade) e na direção da ordem de 0,3. Comprovou-se que as medidas de radar são equivalentes ao de radiossondagem, com o benefício de poder ter dados contínuos, provando-se que as observações, a partir da sua utilização deve desempenhar um papel importante no estudo da baixa atmosfera tropical. From the surface, radiosonde and Doppler radar Band - L data in Serpong, Indonesia (6° 24 ‘ S - 106° 42’ E), measured were performed during drought (1993) and rainy (1994) seasons, when BLAT characteristics were studied. Radar data were validated with soundings through statistical methods (correlation index, average and standard deviation). BLAT structure were interpreted through radar echo (wind), continuously observed through day over study period. BLAT evident characteristics in this region had been associated to diurnal ML (Mixing Layer) that reached 0.3 km at morning and 3-5 km at afternoon, were observed a steady and growth diurnal cycle, due to heating and cooling surface. Main characteristics between seasons were at 0300 LT (Local Time) presents intensity and direction of wind behaviors, but still remained during day an ample distinction between them. In drought season, intensity and direction of wind were more changeable than rainy season, result observed in BLAT height. Acquired information under BLR (Boundary Layer Radar), shown the existence of pronounced diurnal sharp variation on BLAT in clear days. Were verified that BLAT diurnal variation had an evident influence to existence of breeze sea circulation confirmed by BLR in 12/10/93 day. Radar data validation were carried through information of soundings and had presented significant resulting, where drought season regression coefficients had varied between 0.83 and 0.94, as much as intensity as direction, and rainy season had been 0.77 - 0.88 (intensity) and in direction they had been in order of 0.3. Proved that radar measures are equivalents to soundings, with benefit to being able continuous data, proving that using observations must be important role in low level tropical atmosphere study.

In the coastal wetland the mud is consist of fine particles, which means that it is characterized by small gap, and heat transfer is obstructed since moisture is found between the gaps. The relationship between net radiation () and soil heat flux() shows a counterclockwise hysteresis cycle, which refer to a time lag behind in the maximal soil heat fluxes. The albedo is independent of seasonal variation of the vegetation canopy which plays very important roles to store and control the heat in the atmospheric surface layer.

The sensitivity of the marine atmospheric boundary layer (MABL) subjected to sea surface temperatures (SST) during the Structure des Echanges Mer-Atmosphere, Proprietes des Heterogeneites Oceaniques: Recherche Experimentale (SEMAPHORE) experiment in 1993 has been studied. Atmospheric analyses produced by the Action de Recherche, Petite Echelle, Grande Echelle (ARPEGE) operational model at the French meteorological weather service assimilated data sets collected between October 7 and November 17, 1993, merged with the Global Telecommunication System (GTS) data. Analyses were validated against independent data from aircraft instruments collected along a section crossing the Azores oceanic front, not assimilated into the model. The responses of the mean MABL in the aircraft cross section to changes in SST gradients of about 1°C/100 km were the presence of an atmospheric front with horizontal gradients of 1°C/100 km and an increase of the wind intensity from the cold to the warm side during an anticyclonic synoptic situation. The study of the spatiotemporal characteristics of the MABL shows that during 3 days of an anticyclonic synoptic situation the SST is remarkably stationary because it is principally controlled by the Azores ocean current, which has a timescale of about 10 days. However, the temperature and the wind in the MABL are influenced by the prevailing atmospheric conditions. The ocean does not appear to react to the surface atmospheric forcing on the timescale of 3 days, whereas the atmospheric structures are modified by local and synoptic-scale advection. The MABL response appears to be much quicker than that of the SSTs. The correlation between the wind and the thermal structure in the MABL is dominated by the ageostrophic and not by the geostrophic component. In particular, the enhancement of the wind on either side of the SST front is mainly due to the ageostrophic component. Although the surface heat fluxes are not the only cause of ageostrophy, the surface buoyancy flux Q b appears to be an important local source.

X-band marine radar was tested out the estimate of precipitation on the basis of rain gauge data and weather radar. This higher frequency radar is capable of measuring precipitation. The high resolution rainfall measurements will be used for run-off simulations and urban drainage applications.

Foram estudados os picos dos gradientes verticais nos perfis termodinâmicos na Camada Limite Atmosferica (CLA), pois estes picos sao fruto de mudancas repentinas no campo de refratividade atmosferica (N) e esta afeta diretamente a propagacao das ondas eletromagneticas. Atraves de dados de Radar Doppler (banda­L) e radiossondagem foram investigados a ocorrencia de dutos atmosfericos na CLA, durante uma campanha de campo intensiva, entre 08-­14-­Outubro de 1993 correspondentes a estacao seca da regiao de Serpong-Indonesia. As caracteristicas superficiais e a variabilidade espacial foram claramente pronunciadas na estrutura da CLA atraves dos dados de radar. Um resultado importante foi a estimativa da altura da CLA atraves dos gradientes de N, constituindo­se uma alternativa promissora em comparacao aos metodos classicos amplamente utilizados na literatura (perfis de temperatura potencial e umidade especifica). Os valores encontrados de refratividade atraves da radiossondagem foram comparados com os ecos de radar, apresentando um resultado satisfatorio. Outro resultado relevante foi a ocorrencia de dutos na CLA, dutos esses de superficie e evaporacao, bem caracterizados pelos perfis de N, mesmo na presenca de uma circulacao de brisa maritima durante o periodo de estudo.

The simple estimation methods of air temperature and specific humidity at the sea surface are investigated using buoy and satellite data. Air temperature and specific humidity obtained by the regression equations are validated through the comparison with sea truth data. And also in order to certify this method, sensible and latent heat fluxes are compared with those of other methods. Bias of air temperature with MCSST is 0.28 degC with 1.5 degC rmse and 0.98 correlation coefficient. Specific humidity estimated indirectly using buoys data shows also fairly good result in terms of -1.42 g kg/sup -1/ bias and 1.75 g kg/sup -1/ rmse, correlation coefficient 0.97. The statistical results for sensible and latent heat fluxes calculated using the marine meteorological elements which are derived by the present method are comparable with those of previous studies.

Two MODIS instruments on board the Terra and Aqua Satellites are operational for global remote sensing of the land, ocean and atmosphere. Atmospheric sounding data with a high spatial resolution from MODIS will provide a wealth of useful information. The vertical air temperature and moisture data were retrieved using the MODIS data, and compared with the radiosonde data obtained in the Korean Peninsula. The correlation coefficients are 0.99 and 0.89 for air temperature and moisture cases, respectively. Air temperature data were relatively good agreement, but the moisture data from MODIS were underestimated