Observations from the satellite microwave sounders play a vital role in measuring the long-term temperature trends for climate change monitoring. Changes in diurnal sampling over time and calibration drift have been the main sources of uncertainties in the satellite-measured temperature trends. We examine observations from the first of a series of U.S. new generation of microwave sounder, the Advanced Technology Microwave Sounder (ATMS), which has been flying onboard the National Oceanic and Atmospheric Administration (NOAA)/NASA Suomi National Polar-orbiting Partnership (SNPP) environmental satellite since late 2011. The SNPP satellite has a stable afternoon orbit that has close to the same local observation time as NASA's Aqua satellite that has been carrying the heritage microwave sounder, the Advanced Microwave Sounding Unit-A (AMSU-A), from 2002 until the present. The similar overpass timing naturally removes most of their diurnal differences. In addition, direct comparison of temperature anomalies between the two instruments shows little or no relative calibration drift for most channels. Our results suggest that both SNPP/ATMS and Aqua/AMSU-A instruments have achieved absolute stability in the measured atmospheric temperatures within 0.04 K per decade. This uncertainty is small enough to allow reliable detection of the temperature climate trends and help to resolve debate on relevant issues. We also analyze AMSU-A observations onboard the European MetOp-A satellite that has a stable morning orbit 8 hours apart from the SNPP overpass time. Their comparison reveals large asymmetric trends between day and night in the lower- and mid-tropospheric temperatures over land. This information could help to improve climate data records for temperature trend detection with improved accuracy. The SNPP satellite will be followed by four NOAA operational Joint Polar Satellite System (JPSS) satellites, providing accurate and stable measurement for decades to come. The primary mission of JPSS is for weather forecasting. Now, with the added feature of stable orbits, JPSS observations can also be used to monitor changes in climate with much lower uncertainty than the previous generation of NOAA operational satellites.

中文翻译：

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新一代美国卫星微波测深仪实现了高辐射稳定性，可进行可靠的气候变化检测。

卫星微波测深仪的观测对于测量气候变化监测的长期温度趋势起着至关重要的作用。昼夜采样随时间的变化和校准漂移一直是卫星测得的温度趋势不确定性的主要来源。我们检查了美国新一代微波探测仪系列中第一个的观测结果，即先进技术微波探测仪（ATMS），该探测器已经在美国国家海洋和大气管理局（NOAA）/美国宇航局Suomi国家极地轨道合作伙伴关系（SNPP）上飞行）卫星，自2011年下半年起开始运行。SNPP卫星的下午轨道稳定，与美国国家航空航天局（NASA）的Aqua卫星在当地的观测时间相近，该卫星一直在使用传统的微波探测仪，即高级微波探测仪-A（AMSU-A），从2002年至今。相似的立交时间自然消除了它们大多数的昼夜差异。此外，直接比较这两种仪器之间的温度异常对大多数通道而言显示很少或没有相对校准漂移。我们的结果表明，SNPP / ATMS和Aqua / AMSU-A仪器在每十年0.04 K以内的大气温度测量中均实现了绝对的稳定性。这种不确定性很小，足以可靠地检测出温度气候趋势，并有助于解决有关问题的辩论。我们还分析了欧洲MetOp-A卫星上的AMSU-A观测结果，该卫星的轨道早于SNPP穿越时间有8个小时处于稳定状态。他们的比较显示，对流层中低层和中层温度昼夜之间存在很大的不对称趋势。该信息可以帮助改善气候数据记录，以提高准确性以进行温度趋势检测。SNPP卫星之后将是四颗NOAA运行中的联合极地卫星系统（JPSS）卫星，可在未来数十年内提供准确而稳定的测量结果。JPSS的主要任务是天气预报。现在，有了稳定轨道的附加功能，JPSS观测也可以用于监测气候变化，其不确定性要比上一代NOAA运行卫星低得多。JPSS的主要任务是天气预报。现在，有了稳定轨道的附加功能，JPSS观测也可以用于监测气候变化，其不确定性要比上一代NOAA运行卫星低得多。JPSS的主要任务是天气预报。现在，有了稳定轨道的附加功能，JPSS观测也可以用于监测气候变化，其不确定性要比上一代NOAA运行卫星低得多。