Four basic types of synoptic‐scale conditions describe the atmospheric structure and variability observed over the Japan Sea during the 1999/2000 winter season: (1) flow of cold Asian air from the northwest, (2) an outbreak of very cold Siberian air from the north and northeast, (3) passage of a weak cyclone over the southern Japan Sea with a cold air outbreak on the backside of the low, and (4) passage of a moderate cyclone along the northwestern side of the Japan Sea. In winter, the Russian coastal mountains and a surface‐air temperature inversion typically block cold surface continental air from the Japan Sea. Instead, the adiabatic warming of coastal mountain lee‐side air results in small air‐sea temperature differences. Occasional outbreaks of very cold Siberian air eliminate the continental surface‐based inversion and stability, allowing very cold air to push out over the Japan Sea for 1–3 days. During these outbreaks, the 0°C surface air isotherm extends well southward of 40°N, the surface heat losses in the center of the Japan Sea can exceed 600 W m−2, and sheet clouds cover most of the Japan Sea, with individual roll clouds extending from near the Russian coast to Honshu. During December through February, 1991–2002, these strong cold‐air outbreak conditions occur 39% of the time and contribute 43% of the net heat loss from the Japan Sea. The average number of strong cold‐air events per winter (November–March) season is 13 (ranging from 5 to 19); the 1999/2000 winter season covered in our measurements was normal.

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ABSTRACT:This paper will present the project RAPIDMAP. The project is part of CONCERT-Japan, an ERA-NET initiative funded through the FP7 INCO project frame for enhancing research cooperation between European countries and Japan on two topics, one of which is Resilience Against Disasters. The project started in June 2013 and has a duration of 2 years. In the paper, we will outline the aims of the project, methodologies and techniques to be developed and some test data. Remote Sensing (RS) and Geographic Information System (GIS) are powerful technologies for collecting useful information on the damages of disasters in short time. However, since many different types of RS data are available (satellite, aerial, UAV, terrestrial), data co-registration, information integration and feature extraction need reliable and advanced methodologies. In the RAPIDMAP project, we will develop practical ways to integrate RS data processing tools in near-real-time and allow users to use this data soon after the disasters by means of WebGIS tools. This will help not only decision makers but also end-users in the disaster area. The key components of this project are: (1) Near-real-time monitoring: the procedure of near-real-time monitoring with satellites as well as Unmanned Airborne Vehicles (UAV) will be set up and demonstrated. (2) Data co-registration: in disasters, various images as well as maps come from different sources. The co-registration of multiple images is a key technology for information integration. In this project, a system to co-register multiple images in near-real-time will be developed. (3) Data fusion and change detection: one of the advantages of RS is to collect information with multiple sensors. Various methods for fusing optical with active microwave (SAR) sensor data for information extraction and change detection will be developed. (4) Decision Support System (DSS) based on WebGIS technologies: the collected and integrated information has to be easily accessible and visible by decision makers and end-users in near-real-time and worldwide. By using WebGIS technologies, wireless networks and portable terminals, a DSS will allow easy access, retrieval and visualization of all information (fused data, images, maps, etc.) in very short time after data collection and processing. The project will be practically tested and demonstrated at the Tohoku area in Japan and another test site, which were recently affected by large disasters.

ABSTRACT:Observation of sea ice thickness is one of key issues to understand regional effect of global warming. One of approaches to monitor sea ice in large area is microwave remote sensing data analysis. However, ground truth must be necessary to discuss the effectivity of this kind of approach. The conventional method to acquire ground truth of ice thickness is drilling ice layer and directly measuring the thickness by a ruler. However, this method is destructive, time-consuming and limited spatial resolution. Although there are several methods to acquire ice thickness in non-destructive way, ground penetrating radar (GPR) can be effective solution because it can discriminate snow-ice and ice-sea water interface. In this paper, we carried out GPR measurement in Lake Saroma for relatively large area (200m by 300m, approximately) aiming to obtain grand truth for remote sensing data.. GPR survey was conducted at 5 locations in the area. The direct measurement was also conducted simultaneously in order to calibrate GPR data for thickness estimation and to validate the result. Although GPR Bscan image obtained from 600MHz contains the reflection which may come from a structure under snow, the origin of the reflection is not obvious. Therefore, further analysis and interpretation of the GPR image, such as numerical simulation, additional signal processing and use of 200MHz antenna, are required to move on thickness estimation.