• Journal of Environmental Science International
• /
• v.20 no.3
• /
• pp.309-319
• /
• 2011

In this study, we investigated the effects of Upo-swamp upon local thermal environment with nighttime cooling rate. To do this, we set up the AWS(Automatic Weather observation System) over the central part of Upo-swamp on the early October 2007. We conducted the study by comparing the AWS data with another weather data observed by several meteorological observations of the Korea Meteorological Administration located at the vicinity of Upo-swamp for one year. The air temperature of Upo-swamp was higher than that of the surrounding in cold-climate season. But it was opposite in warm-climate season. We confirmed that Upo-swamp roles to mitigate the daily and annual air temperature ranges. And the daily air temperature variation of Upo-swamp lagged behind the land one. This phenomenon represent that the heat reservoir capacity of Upo-swamp is much larger than that of the ground.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.12 no.1
• /
• pp.11-18
• /
• 2000

On the 25th of November in 1997 winter season, unprecedented high waves were recorded at the southern part of Korea Peninsular. The significant wave heights over 4 m were recorded at Marado, Pusan and Ulrungdo successively with time lags. Seoguipo breakwaters which were under construction were damaged by the unexpected high waves. These unprecedented southerly high waves in winter seem to be caused by unusual development and traveling of low pressure. Weather charts and wave fields calculated by a numerical model were analyzed to examine the unusual development of these waves. Protection against the southerly high waves in winter must be considered in coastal constructions and structures.

• Atmosphere
• /
• v.21 no.1
• /
• pp.95-108
• /
• 2011

The effects of an apartment complex on flow and pollutant dispersion in an urban area are numerically investigated using a computational fluid dynamics (CFD) model. The CFD model is based on the Reynolds-averaged Navier-Stokes equations and includes the renormalization group k-${\varepsilon}$ turbulence model. The geographic information system (GIS) data is used as an input data of the CFD model. Eight numerical simulations are carried out for different inflow directions and, for each inflow direction, the effects of an apartment complex are investigated, comparing the characteristics of flow and dispersion before and after construction of the apartment complex in detail. The observation data of automatic weather system (AWS) is analyzed. The windrose analysis shows that the wind speed and direction after the construction of the complex are quite different from those before the construction. The construction of the apartment complex resulted in the decrease in wind speed at the downwind region. It is also shown that the wind speed increased partially inside the apartment complex due to the channeling effect to satisfy the mass continuity. On the whole, the wind speed decreased at the downwind region due to the drag effect by the apartment complex. As a result, the passive pollutant concentration increased (decreased) near the downwind region of (within) the apartment complex compared with that before the construction.

• Journal of the Korea Convergence Society
• /
• v.9 no.3
• /
• pp.15-21
• /
• 2018

The ocean drifter is a device for observing the ocean weather by floating off the sea surface. The data observed through the drifter is utilized in the ocean weather prediction and oil spill. Observed data may contain incorrect or missing data at the time of observation, and accuracy may be lowered when we use the data. In this paper, we propose a data correction model using recurrent neural networks. We corrected data collected from 7 drifters in 2015 and 8 drifters in 2016, and conducted experiments of drifter moving prediction to reflect the correction results. Experimental results showed that observed data are corrected by 13.9% and improved the performance of the prediction model by 1.4%.

• Journal of Environmental Science International
• /
• v.28 no.11
• /
• pp.1047-1059
• /
• 2019

To address the increase of weather hazards and the emergence of new types of such hazards, an optimization technique for three-dimensional (3D) representation of meteorological facts and atmospheric information was examined in this study as a novel method for weather analysis. The proposed system is termed as "meteorological and air quality information visualization engine" (MAIVE), and it can support several file formats and can implement high-resolution 3D terrain by employing a 30 m resolution digital elevation model. In this study, latest 3D representation techniques such as wind vector fields, contour maps, stream vector, stream line flow along the wind field and 3D volume rendering were applied. Implementation of the examples demonstrates that the results of numerical modeling are well reflected, and new representation techniques can facilitate the observation of meteorological factors and atmospheric information from different perspectives.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2004.06a
• /
• pp.3-17
• /
• 2004

Space-borne Earth observation technique is one of the most cost effective and rapidly advancing Earth science research tools today and the potential field and micro-wave radar applications have been leading the discipline. The traditional optical imaging systems including the well known Landsat, NOAA - AVHRR, SPOT, and IKONOS have steadily improved spatial imaging resolution but increasing cloud covers have the major deterrent. The new Earth observation satellites ENVISAT (launched on March 1 2002, specifically for Earth environment observation), ALOS (planned for launching in 2004 - 2005 period and ALOS stands for Advanced Land Observation Satellite), and RADARSAT-II (planned for launching in 2005) all have synthetic aperture radar (SAR) onboard, which all have partial or fully polarimetric imaging capabilities. These new types of polarimetric imaging radars with repeat orbit interferometric capabilities are opening up completely new possibilities in Earth system science research, in addition to the radar altimeter and scatterometer. The main advantage of a SAR system is the all weather imaging capability without Sun light and the newly developed interferometric capabilities, utilizing the phase information in SAR data further extends the observation capabilities of directional surface covers and neotectonic surface displacements. In addition, if one can utilize the newly available multiple frequency polarimetric information, the new generation of space-borne SAR systems is the future research tool for Earth observation and global environmental change monitoring. The potential field strength decreases as a function of the inverse square of the distance between the source and the observation point and geophysicists have traditionally been reluctant to make the potential field observation from any space-borne platforms. However, there have recently been a number of potential field missions such as ASTRID-2, Orsted, CHAMP, GRACE, GOCE. Of course these satellite sensors are most effective for low spatial resolution applications. For similar objects, AMPERE and NPOESS are being planned by the United States and France. The Earth science disciplines which utilize space-borne platforms most are the astronomy and atmospheric science. However in this talk we will focus our discussion on the solid Earth and physical oceanographic applications. The geodynamic applications actively being investigated from various space-borne platforms geological mapping, earthquake and volcano .elated tectonic deformation, generation of p.ecise digital elevation model (DEM), development of multi-temporal differential cross-track SAR interferometry, sea surface wind measurement, tidal flat geomorphology, sea surface wave dynamics, internal waves and high latitude cryogenics including sea ice problems.

• 한국방재학회:학술대회논문집
• /
• 2011.02a
• /
• pp.172-172
• /
• 2011

The interaction between land surface and atmosphere is essentially affected by hydrometeorological variables including soil moisture. Accurate estimation of soil moisture at spatial and temporal scales is crucial to better understand its roles to the weather systems. The KLDAS(Korea Land Data Assimilation System) is a regional, specifically Korea peninsula land surface information systems. As other prior land data assimilation systems, this can provide initial soil field information which can be used in atmospheric simulations. For this study, as an enabling high-resolution tool, weather research and forecasting(WRF-ARW) model is applied to produce precipitation data using GFS(Global Forecast System) with GFS embedded and KLDAS soil moisture information as initialization data. WRF-ARW generates precipitation data for a specific region using different parameters in physics options. The produced precipitation data will be employed for simulations of Hydrological Models such as HEC(Hydrologic Engineering Center) - HMS(Hydrologic Modeling System) as predefined input data for selected regional water responses. The purpose of this study is to show the impact of a hydrometeorological variable such as soil moisture in KLDAS on hydrological consequences in Korea peninsula. The study region, Chongmi River Basin, is located in the center of Korea Peninsular. This has 60.8Km river length and 17.01% slope. This region mostly consists of farming field however the chosen study area placed in mountainous area. The length of river basin perimeter is 185Km and the average width of river is 9.53 meter with 676 meter highest elevation in this region. We have four different observation locations : Sulsung, Taepyung, Samjook, and Sangkeug observatoriesn, This watershed is selected as a tentative research location and continuously studied for getting hydrological effects from land surface information. Simulations for a real regional storm case(June 17~ June 25, 2006) are executed. WRF-ARW for this case study used WSM6 as a micro physics, Kain-Fritcsch Scheme for cumulus scheme, and YSU scheme for planetary boundary layer. The results of WRF simulations generate excellent precipitation data in terms of peak precipitation and date, and the pattern of daily precipitation for four locations. For Sankeug observatory, WRF overestimated precipitation approximately 100 mm/day on July 17, 2006. Taepyung and Samjook display that WRF produced either with KLDAS or with GFS embedded initial soil moisture data higher precipitation amounts compared to observation. Results and discussions in detail on accuracy of prediction using formerly mentioned manners are going to be presented in 2011 Annual Conference of the Korean Society of Hazard Mitigation.

• Atmosphere
• /
• v.26 no.2
• /
• pp.347-356
• /
• 2016

Radiosonde is an observation equipment that measures pressure (geopotential height), temperature, relative humidity and wind by being launched up from the ground. Radiosonde data which serves as an important element of weather forecast and research often causes a bias in a model output due to accuracy and sensitivity between the different manufacturers. Although Korean Meteorological Administration (KMA) and several institutes have conducted routine and intensive radiosonde observations, very few studies have been done before on the characteristics of radiosonde performance. Analyzing radiosonde observation data without proper understanding of the unique nature of those sensors may lead to a significant bias in the analysis of results. To evaluate performance and reliability of radiosonde, we analyzed the differences between two sensors made by the different manufacturers, which have been used in the campaign of Experiment on Snow Storm At Yeongdong (ESSAY). We improved a couple of methods to launch the balloon being attached with the sensors. Further we examined cloud-layer impacts on temperature and humidity differences for the analysis of both sensors' performance among various weather conditions, and also compared daytime and nighttime profiles to understand temporal dependence of meteorological sensors. The overall results showed that there are small but consistent biases in both temperature and humidity between different manufactured sensors, which could eventually secure reliable precisions of both sensors, irrespective of accuracy. This study would contribute to an improved sounding of atmospheric vertical states through development and improvement of the meteorological sensors.

• The Korean Journal of Quaternary Research
• /
• v.14 no.2
• /
• pp.117-123
• /
• 2000

This study examined the spatial distribution of precipitation in Sokcho area. The hourly, daily and monthly precipitation on the 2 stations, 5 AWS in Sokcho area were analyzed by daily, monthly, altitudinal distribution and synoptic environment. The results of the Study are as follows. The amount of Yearly precipitation, 1970~1999 in Sokcho area is gradually increasing. The amount of monthly precipitation 1970~1999 at Sorak weather observation station (altitude 148m), Compared with that in 7 Stations is greatest in spring, Summer and autumn. Because the valleys near Ssangcheon river are funnels for sea wind into Sorak weather observation station. The amount of Summerly precipitation at Mishiryong(1993~1999), the highest altitude in 7 weather observations stations is more 95.2mm than that of Sokcho airport, the lowest altitude, but the amount of winterly precipitation at Sokcho airport is more 89.6mm than that of Mishiryong. When the heavy rainfall and the heavy Snowfall occured in Sokcho area, wind systems were mainly a sea wind (north-north-eastly wind, north-westly wind) and daily mean wind speed was respectively 4.4㎧, 3.6㎧. The amount of the heavy rainfall and heavy snow fall in Sokcho area is closely associated with the north-eastly stream at the lower and the upper level toward the coast of East sea(Sokcho area).

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.8
• /
• pp.3925-3942
• /
• 2016

Like natural climate change on the planet earth, the climate in software development environments is also changing (fast). Like the natural weather, the software environment is also disruptive. As the climate experts alert and suggest taking necessary measures to overcome certain challenges to make this earth a safer and comfortable living place, likewise this article also alerts the relevant stakeholders of software craftsmanship about the dynamic challenges that traditional Software Engineering (SE) with purely "Engineering mind-set" is not capable to respond. Hence, some new thoughts to overcome such challenges are shared. Fundamentally, based on the historical evidences, this article presents the authors' observation about continuous shift from traditional "Engineering-based" software development approaches to disruptive approaches - "Vibrant Softology". The authors see the cause of this shift as disruptive transformational force, which is so powerful that it is uncontrollably diminishing the "Engineering-based" approach from software development environments. The authors align it with climate change analogy. Based on this analogy, the authors feel the need to theoretically re-coin the notion of SE to some new term; perhaps Vibrant/Dynamic Softology (VS or DS). Hence, the authors suggest "a new (disruptive and dynamic) way of thinking is required to develop software". It is worth mentioning that the purpose of article and this new theory is not to disparage the notion of software engineering altogether, rather the aim is to highlight the importance of transformation from SE to its next level (perhaps VS/DS) due to the emerging needs in the software craftsmanship environment.