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An analysis of simulated future surface climate change over the southern half of Korean Peninsula using a RegCM3-based high-resolution
one-way double-nested system is presented. Changes in mean climate as well as the frequency and intensity of extreme climate
events are discussed for the 30-year-period of 2021–2050 with respect to the reference period of 1971–2000 based on the IPCC
SRES B2 emission scenario. Warming in the range of 1–4°C is found throughout the analysis region and in all seasons. The warming
is maximum in the higher latitudes of the South Korean Peninsula and in the cold season. A large reduction in snow depth is
projected in response to the increase of winter minimum temperature induced by the greenhouse warming. The change in precipitation
shows a distinct seasonal variation and a substantial regional variability. In particular, we find a large increase of wintertime
precipitation over Korea, especially in the upslope side of major mountain systems. Summer precipitation increases over the
northern part of South Korea and decreases over the southern regions, indicating regional diversity. The precipitation change
also shows marked intraseasonal variations throughout the monsoon season. The temperature change shows a positive trend throughout
2021–2050 while the precipitation change is characterized by pronounced interdecadal variations. The PDF of the daily temperature
is shifted towards higher values and is somewhat narrower in the scenario run than the reference one. The number of frost
days decreases markedly and the number of hot days increases. The regional distribution of heavy precipitation (over 80 mm/day)
changes considerably, indicating changes in flood vulnerable regions. The climate change signal shows pronounced fine scale
signal over Korea, indicating the need of high-resolution climate simulations 相似文献
43.
Using an intermediate ocean–atmosphere coupled model (ICM) for the tropical Pacific, we investigated the role of the ocean dynamical thermostat (ODT) in regulating the tropical eastern Pacific sea surface temperature (SST) under global warming conditions. The external, uniformly distributed surface heating results in the cooling of the tropical eastern Pacific “cold tongue,” and the amplitude of the cooling increases as more heat is added but not simply linearly. Furthermore, an upper bound for the influence of the equatorially symmetric surface heating on the cold tongue cooling exists. The additional heating beyond the upper bound does not cool the cold tongue in a systematic manner. The heat budget analysis suggests that the zonal advection is the primary factor that contributes to such nonlinear SST response. The radiative heating due to the greenhouse effect (hereafter, RHG) that is obtained from the multi-model ensemble of the Climate Model Intercomparison Project Phase III (CMIP3) was externally given to ICM. The RHG obtained from the twentieth century simulation intensified the cold tongue cooling and the subtropical warming, which were further intensified by the RHG from the doubled CO2 concentration simulation. However, the cold tongue cooling was significantly reduced and the negative SST response region was shrunken toward the equator by the RHG from the quadrupled CO2 concentration simulation, while the subtropical warming increased further. A systematic RHG forced experiment having the same spatial pattern of RHG from doubled CO2 concentration simulation with different amplitude of forcing revealed that the ocean dynamical response to global warming tended to enhance the cooling in the tropical eastern Pacific by virtue of meridional advection and upwelling; however, these cooling effects could not fully compensate a given RHG warming as the external forcing becomes larger. Moreover, the feedback by the zonal thermal advection actually exerted the warming over the equatorial region. Therefore, as the global warming is intensified, the cooling over the eastern tropical Pacific by ODT and the negative SST response area are reduced. 相似文献
44.
The effect of topography and sea surface temperature on heavy snowfall in the Yeongdong region: A case study with high resolution WRF simulation 总被引:1,自引:0,他引:1
Sun-Hee Jung Eun-Soon Im Sang-Ok Han 《Asia-Pacific Journal of Atmospheric Sciences》2012,48(3):259-273
An analysis of the heavy snowfall that occurred on 11?C14 February 2011 in the Yeongdong region along the eastern coast is presented. Relevant characteristics based on observation and model simulations are discussed with a focus on the times of maximum snowfall in Gangneung (GN) and Daegwallyong (DG). This event was considered part of the typical snowfall pattern that frequently occurs in the Yeongdong region due to the prevailing northeasterly flow. The control simulation using the high resolution Weather Research and Forecasting (WRF) model (1 km × 1 km) showed reasonable performance in capturing the spatial distribution and temporal evolution of precipitation. The area of precipitation maxima appeared to propagate from the plain coastal region further into the inland mountainous region, in relation to the location of convergence zone. In addition, a series of sensitivity experiments were performed to investigate the effect of topography and sea surface temperature (SST) on the formation of heavy snowfall. The change of topography tended to modulate the topographically induced mechanical flow, and thereby modify the precipitation distribution, which highlights the importance of an elaborate representation of the topography. On the other hand, the sensitivity experiment to prescribe positive (negative) SST forcing shows the enhanced (suppressed) precipitation amount due to the change of the sensible and latent heat fluxes. 相似文献
45.
Support vector machines in remote sensing: A review 总被引:19,自引:0,他引:19
Giorgos Mountrakis Jungho Im Caesar Ogole 《ISPRS Journal of Photogrammetry and Remote Sensing》2011,66(3):247-259
A wide range of methods for analysis of airborne- and satellite-derived imagery continues to be proposed and assessed. In this paper, we review remote sensing implementations of support vector machines (SVMs), a promising machine learning methodology. This review is timely due to the exponentially increasing number of works published in recent years. SVMs are particularly appealing in the remote sensing field due to their ability to generalize well even with limited training samples, a common limitation for remote sensing applications. However, they also suffer from parameter assignment issues that can significantly affect obtained results. A summary of empirical results is provided for various applications of over one hundred published works (as of April, 2010). It is our hope that this survey will provide guidelines for future applications of SVMs and possible areas of algorithm enhancement. 相似文献
46.
Natural Hazards - This study investigates the capability of two numerical models, namely the Weather Research and Forecasting (WRF) and Cloud Resolving Storm Simulator (CReSS), to simulate the... 相似文献
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Gil Young Kim Gwang Soo Lee Dong Geun Yoo Young Kyo Seo Im Hak Kim 《Marine Georesources & Geotechnology》2018,36(3):264-270
The KISAP (Korea Institute of Geoscience and Mineral Resources Seafloor Acoustic Probe) was developed to obtain in situ compressional wave velocity and attenuation profiles for seafloor sediments. The instrument comprises recording channel receivers, and an acoustic source, and can be attached to a corer or a probe. Here, we report experiments comparing KISAP in situ velocity to laboratory velocity of colocated piston cores. KISAP data matched laboratory data (corrected for temperature and pressure) reasonably. KISAP can be used to collect in situ acoustic data and can be effectively used to calibrate previous laboratory data to in situ data. 相似文献
49.
Detecting areal changes in tidal flats after sea dike construction using Landsat-TM images 总被引:1,自引:0,他引:1
Moon Seong Kang Sang June Im Tae Il Jang Seung Woo Park Sang Min Kim 《Journal of Earth System Science》2007,116(6):561-573
The main objective of this study was to estimate changes in the area of tidal flats that occurred after sea dike construction
on the western coast of South Korea using Landsat-TM images. Applying the ISODATA method of unsupervised classification for
Landsat-TM images, the tidal flats were identified, and the resulting areas were quantified for each image. The area of tidal
flats from a topographic map published in one year differs significantly from that shown in another, which appears to be attributable
to the tide levels at the time of aerial photography. During the study period, the area of tidal flats, as estimated from
Landsat-TM images, increased by 4.57 km2 per year in the study areas. The tidal flats in the inner sea of Chunsu Harbor area increased by 200 m2 per zone, while the accumulation for a number of inner sea areas within Asan Harbor area occurred at over 50m2 per zone. The results of this research may serve as the basis of an environmentallyfriendly development plan for tidal flats. 相似文献
50.
Comparing groundwater recharge and base flow in the Bukmoongol small-forested watershed,Korea 总被引:1,自引:0,他引:1
E. A. Combalicer S. H. Lee S. Ahn D. Y. Kim S. Im 《Journal of Earth System Science》2008,117(5):553-566
Groundwater recharge and base flow using different investigated methods are simulated in the 15-ha Bukmoongol small-forested
watershed located at the southern part of Korea. The WHAT system, PART, RORA, PULSE, BFI, and RAP software are used to estimate
groundwater recharge or base flow and base flow index from the measured streamflow. Results show that about 15–31 per cent
of annual rainfall might be contributed for base flow. The watershed groundwater recharge proportions are computed to about
10–21 per cent during the wet period and 23–32 per cent for the remainder periods. Mean annual base flow indices vary from
0.25 to 0.76 estimated using different methods. However, the study found out that all methods were significantly correlated
with each other. The similarity of various methods is expressed as a weighted relationship provided by the matrix product
from the principal component analysis. Overall, the BFI and WHAT software appeared consistent in estimating recharge or base
flow, and base flow index under Korea’s conditions. The case study recommends the application of different models to other
watersheds as well as in low-lying areas where most observation groundwater wells are located with available streamflow data. 相似文献