本数据集为K&Ka波段机载微波辐射计于2008年03月30日获取，地点在冰沟飞行区。\n
其中K波段频率为18.7GHz，天顶角观测，无极化信息；Ka波段频率为36.0GHz，扫描成像，扫描范围±12°，垂直极化观测。飞机12:43（北京时间，下同）从张掖机场起飞，15:44降落。13:20开始对冰沟摄区进行观测，因气流太大，飞行稳定性无法保证，故只飞行了11条航线，14:50撤出测区。在观测期间，飞行高度5000m左右，飞行速度220-250km/hr左右。\n
原始数据分为两部分，分别为微波辐射计数据和GPS数据。其中微波辐射计K波段属非成像观测，由文本文件记录瞬时观测获得的数码值。Ka波段属成像观测，与L和K波段数据不同，Ka波段原始记录为十六进制文本文件，在数据处理时需要首先将十六进制的文件转换为十进制，进而获得24度的扫描范围内均匀采集的112个数据（每两个数据点的角度差为24/112=0.214度）。\n
GPS数据记录飞行时的经纬度以及飞机姿态参数等。使用微波辐射计观测数据时需要根据定标系数将记录的数码值转换为亮温值（定标系数文件与原始观测数据归档在一起）。同时，通过微波辐射计和GPS各自的时钟记录，可以将微波观测与GPS记录联系起来，给微波观测匹配地理坐标信息，Ka波段数据处理时还需要考虑角度扫描效应，对扫描周期内的112个数据分别赋予地理坐标信息。\n
由于微波辐射计观测分辨率较粗，数据处理中一般忽略飞机的航偏、翻滚以及俯仰效应。根据使用目标及飞行相对航高（H），在定标和坐标匹配后，还可以将观测信息栅格化，K波段的分辨率（x）与观测足迹（footprint）可以认为一致，参考分辨率为：x=0.24H；Ka波段分辨率为39m。经过以上各步处理后，可以获得用户能够直接使用的产品。", "ds_source": "
2008年3月30日在冰沟流域加密观测区开展的K&Ka波段机载微波辐射计的地面同步观测，为积雪微波辐射特性及参数反演，尤其是干湿雪的判别研究提供了基本数据集。", "ds_process_way": "
\n观测内容包括：\n
\n1）雪特性分析仪观测，参数包括有雪密度、雪复介电常数、雪体积含水量、雪重量含水量等，该测量在样地BG-A进行。\n
\n2）积雪参数观测，包括雪深观测、飞机过境时同步的雪表面温度观测、分层的雪深温度观测、雪粒径观测、雪密度观测。\n
\n该观测分别在5个样地BG-A、BG-B、BG-F、BG-H、BG-I进行。其中BG-A测量10个点，BG-B测量6个点，BG-F测量12个点，BG-H测量21个点，BG-I测量20个点。\n
\n具体测量方法和使用的仪器如下：在每一个测量点挖积雪剖面，自上而下每10cm均匀分层，如果最后剩下的深度超过10cm而不足15cm则以一层划分。分别测量每层的厚度、雪粒径、密度、温度。每层厚度有塑料直尺量出；雪粒径有手持显微镜人工读数；每一层随机测量三次；密度由每层的环刀采取雪样计算得到；温度由针式温度计测量得到，每一层积雪温度由同时测量的两个针式温度计的平均值决定。并且同时在I样地和H样地于飞机过境时同步测量雪表面温度。
", "ds_quality": "\n数据质量良好
", "ds_acq_start_time": "2008-03-30 00:00:00", "ds_acq_end_time": "2008-03-31 00:00:00", "ds_acq_place": "黑河流域,上游寒区水文试验区, 冰沟流域加密观测区", "ds_acq_lon_east": 100.44305555555556, "ds_acq_lat_south": 38.04333333333333, "ds_acq_lon_west": 100.58972222222222, "ds_acq_lat_north": 38.973888888888894, "ds_acq_alt_low": null, "ds_acq_alt_high": null, "ds_share_type": "apply-access", "ds_total_size": 25716464, "ds_files_count": 2, "ds_format": "excel", "ds_space_res": null, "ds_time_res": "时", "ds_coordinate": "WGS84", "ds_projection": "", "ds_thumbnail": "acc71e2e-8445-4a02-b71f-bfea92d2e989.png", "ds_thumb_from": 0, "ds_ref_way": "梁继, 王树果, 车涛, 肖青，黑河综合遥感联合试验：冰沟流域飞行区K&Ka波段机载微波辐射计数据集（2008年3月30日），国家冰川冻土沙漠科学数据中心(www.ncdc.ac.cn)，2019，doi：10.12072/ncdc.NIEER.db1836.2022", "paper_ref_way": "", "ds_ref_instruction": "本数据由“黑河综合遥感联合试验”产生，用户在使用数据时请在正文中明确声明数据的来源，并在参考文献部分引用本元数据提供的引用方式。", "ds_from_station": null, "organization_id": "14df1d8b-6362-4c0f-b88e-b46d4abe5db9", "ds_serv_man": "敏玉芳", "ds_serv_phone": "0931-4967596", "ds_serv_mail": "ncdc@lzb.ac.cn", "doi_value": "10.12072/ncdc.NIEER.db1836.2022", "subject_codes": null, "quality_level": 3, "publish_time": "2022-03-15 15:11:01", "last_updated": "2022-03-15 15:11:01", "protected": false, "protected_to": null, "lang": "zh", "cstr": "11738.11.ncdc.NIEER.2021.1874", "i18n": { "en": { "title": "Heihe River Integrated Remote Sensing joint test: K & Ka band airborne microwave radiometer data set in Binggou River Basin flight area (March 30, 2008)", "ds_format": "", "ds_source": "K & amp carried out in the intensive observation area of Binggou basin on March 30, 2008; The ground synchronous observation of Ka band airborne microwave radiometer provides a basic data set for snow microwave radiation characteristics and parameter inversion, especially for the discrimination of dry and wet snow.", "ds_quality": "
\nGood data quality
", "ds_ref_way": "", "ds_abstract": "This data set was acquired by K & Ka band airborne microwave radiometer on March 30, 2008 at Binggou flight area.\n
The K-band frequency is 18.7ghz, zenith angle observation, no polarization information; Ka band frequency is 36.0ghz, scanning imaging, scanning range ± 12 °, vertical polarization observation. The plane took off from Zhangye airport at 12:43 (Beijing time, the same below) and landed at 15:44. 13: At the beginning of the 20th, we began to observe the ice trench photographing area. Because the air flow was too large and the flight stability could not be guaranteed, we only flew 11 routes and withdrew from the measuring area at 14:50. During the observation period, the flight altitude is about 5000m and the flight speed is about 220-250km / hr.\n
The original data is divided into two parts: microwave radiometer data and GPS data. The K-band microwave radiometer belongs to non imaging observation, and the digital value obtained from instantaneous observation is recorded by text file. Ka band belongs to imaging observation. Different from L-band and K-band data, the original record of Ka band is a hexadecimal text file. During data processing, the hexadecimal file needs to be converted into decimal, so as to obtain 112 data uniformly collected within the scanning range of 24 degrees (the angle difference of each two data points is 24 / 112 = 0.214 degrees).\n
GPS data records longitude and latitude during flight and aircraft attitude parameters. When using microwave radiometer observation data, it is necessary to convert the recorded digital value into bright temperature value according to the calibration coefficient (the calibration coefficient file is archived with the original observation data). At the same time, through the respective clock records of microwave radiometer and GPS, microwave observation can be connected with GPS record to match geographic coordinate information for microwave observation. When processing Ka band data, it is also necessary to consider the angle scanning effect and give geographic coordinate information to 112 data in the scanning cycle.\n
Due to the coarse observation resolution of microwave radiometer, the yaw, roll and pitch effects of aircraft are generally ignored in data processing. According to the use target and flight relative altitude (H), after calibration and coordinate matching, the observation information can also be rasterized. The resolution (x) of K-band can be considered to be consistent with the observation footprint, and the reference resolution is: x = 0.24h; Ka band resolution is 39m. After the above steps, the products that users can use directly can be obtained.
", "ds_time_res": "时", "ds_acq_place": "Heihe River Basin, upstream cold region hydrological test area, Binggou basin intensive observation area", "ds_space_res": "", "ds_projection": "", "ds_process_way": "\nObservation contents include:\n
\n1) The parameters observed by snow characteristic analyzer include snow density, snow complex dielectric constant, snow volume water content, snow weight water content, etc. the measurement is carried out in sample plot bg-a.\n
\n2) Snow parameter observation, including snow depth observation, synchronous snow surface temperature observation during aircraft transit, layered snow depth temperature observation, snow particle size observation and snow density observation.\n
\nThe observation was carried out in 5 sample plots bg-a, bg-b, bg-f, bg-h and bg-i. There are 10 points measured by bg-a, 6 points measured by bg-b, 12 points measured by bg-f, 21 points measured by bg-h and 20 points measured by bg-i.\n
\nThe specific measurement methods and instruments used are as follows: dig the snow section at each measurement point, and evenly layer every 10cm from top to bottom. If the last remaining depth is more than 10cm but less than 15cm, it shall be divided into one layer. Measure the thickness, snow particle size, density and temperature of each layer respectively. The thickness of each layer is measured with a plastic ruler; Manual reading of snow particle size with hand-held microscope; Three random measurements for each layer; The density is calculated from the snow sample taken by the ring knife of each layer; The temperature is measured by the needle thermometer, and the temperature of each layer of snow is determined by the average value of two needle thermometers measured at the same time. At the same time, the snow surface temperature is measured simultaneously in sample I and sample h when the aircraft passes through.
", "ds_ref_instruction": " " } }, "submit_center_id": "ncdc", "data_level": 0, "license_type": "CC BY 4.0", "doi_reg_from": "reg_local", "cstr_reg_from": "reg_local", "doi_not_reg_reason": null, "cstr_not_reg_reason": null, "is_paper_in_submitting": false, "ds_topic_tags": [ "机载", "地面遥感", "微波辐射计" ], "ds_subject_tags": [ "地理学" ], "ds_class_tags": [], "ds_locus_tags": [ "上游寒区水文试验区", "黑河流域" ], "ds_time_tags": [ 2008 ], "ds_contributors": [ { "true_name": "梁继", "email": "leung@lzb.ac.cn", "work_for": "中国科学院西北生态环境资源研究院", "country": "中国" }, { "true_name": "王树果", "email": "sgwang@lzb.ac.cn", "work_for": "中国科学院西北生态环境资源研究院", "country": "中国" }, { "true_name": "车涛", "email": "chetao@lzb.ac.cn", "work_for": "中国科学院西北生态环境资源研究院", "country": "中国" }, { "true_name": "肖青", "email": "xiaoqing@irsa.ac.cn", "work_for": "中国科学院遥感与数字地球研究所", "country": "中国" } ], "ds_meta_authors": [ { "true_name": "梁继", "email": "leung@lzb.ac.cn", "work_for": "中国科学院西北生态环境资源研究院", "country": "中国" } ], "ds_managers": [ { "true_name": "梁继", "email": "leung@lzb.ac.cn", "work_for": "中国科学院西北生态环境资源研究院", "country": "中国" } ], "category": "遥感及产品" }