Radar monitoring data collected at two locations in June, 2009, Breidamerkurjokull

5-MHz ground-based radar system was located on two places on Breidamerkurjokull for several days to measure temporal changes of englacial and subglacial properties. The data file includes two structures: Site A and Site B. Each structure includes two radar waveforms (ch0 for a wider amplitude range and ch1 for a narrower amplitude range), corresponding two-way travel time, and time when each radar data was collected (julian day, hour, minute, second, and timestamp = jday + (hour + minute./60 + second./3600)./24). We replaced the batteries of the radar system every day, which is not frequent enough to collect the data continuously. The users of this dataset should pay attention to temporal changes of the radar-transmitting power. Amplitudes of the direct wave can be used to measure this feature caused by decreased voltage of the power supply. Coordinates of two monitoring sites are: Site A: 64.0961N, 16.3441W (WGS84 decimal degrees) Site B: 64.0891N, 16.3357W (WGS84 decimal degrees)5兆赫兹地基雷达（ground-based radar）系统于布雷德梅尔克约库尔冰川（Breidamerkurjokull）的两个监测点位布设数日，用于探测冰内（englacial）与冰下（subglacial）属性的时序变化。 本数据文件包含两类存储结构：A测点（Site A）与B测点（Site B）。每类结构均包含两组雷达波形（通道0（ch0）对应更宽的幅度范围，通道1（ch1）对应更窄的幅度范围）、对应的双程走时，以及雷达数据采集时刻信息，具体包含儒略日、时、分、秒，时间戳计算公式为：timestamp = jday + (hour + minute/60 + second/3600)/24。 研究团队每日为雷达系统更换电池，但该更换频率不足以实现数据的连续采集。 本数据集使用者需留意雷达发射功率的时序变化特征，可通过直达波的幅度值，表征供电电压降低引发的发射功率衰减情况。 两个监测点位的坐标信息如下：A测点（Site A）：64.0961°N，16.3441°W（WGS84十进制度坐标系）；B测点（Site B）：64.0891°N，16.3357°W（WGS84十进制度坐标系）。