Comparison between POES energetic electron precipitation observations and riometer absorptions: Implications for determining true precipitation fluxes
Comparison between POES energetic electron precipitation observations and riometer absorptions: Implications for determining true precipitation fluxes
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POES 高能电子降水观测与测力计吸收之间的比较：对确定真实降水通量的影响
DOI：
10.1002/2013ja019439
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Rodger C
中科院分区：
文献类型：
--
作者：
Rodger C
高能电子沉淀（EEP）影响中层大气的化学成分，越来越多的证据表明它与高纬度地区的地表温度相耦合。为了更好地理解这种联系，必须进行现实的观测，以正确描述降水，并将其纳入化学气候模型。极轨运行环境卫星（POES）探测器测量降水粒子，但仅测量积分通量，并且仅测量反弹损失锥的一小部分。地基riometers响应整个反弹损失锥的降水;它们测量宇宙无线电噪声吸收（CNA），这是一种定性代理，缺乏关于EEP能量通量的直接信息。POES观测应该与ΔCNA有直接关系，比较两者将阐明它们在大气变化研究中的效用。我们确定了电离层的变化所产生的EEP测量的POES航天器在~250立交桥的成像riometer在北方芬兰。当大于30 keV的通量被报告为<106 cm −2s− 1 sr −1时，从POES数据模拟的ΔCNA比观测到的ΔCNA小10-15倍。在这个水平之上，天基和地基测量之间存在相对较好的一致性。这种差异主要发生在低地磁活动期间，我们认为，弱扩散是主导的俯仰角散射到反弹损失锥在这些时候。使用测量的捕获通量的计算校正大大减少了差异，并提供了进一步的支持，我们的假设，弱扩散导致低估的EEP。
Energetic electron precipitation (EEP) impacts the chemistry of the middle atmosphere with growing evidence of coupling to surface temperatures at high latitudes. To better understand this link, it is essential to have realistic observations to properly characterize precipitation and which can be incorporated into chemistry‐climate models. The Polar‐orbiting Operational Environmental Satellite (POES) detectors measure precipitating particles but only integral fluxes and only in a fraction of the bounce loss cone. Ground‐based riometers respond to precipitation from the whole bounce loss cone; they measure the cosmic radio noise absorption (CNA), a qualitative proxy with scant direct information on the energy flux of EEP. POES observations should have a direct relationship with ΔCNA and comparing the two will clarify their utility in studies of atmospheric change. We determined ionospheric changes produced by the EEP measured by the POES spacecraft in ~250 overpasses of an imaging riometer in northern Finland. The ΔCNA modeled from the POES data is 10–15 times less than the observed ΔCNA when the >30 keV flux is reported as <106cm−2s−1sr−1. Above this level, there is relatively good agreement between the space‐based and ground‐based measurements. The discrepancy occurs mostly during periods of low geomagnetic activity, and we contend that weak diffusion is dominating the pitch angle scattering into the bounce loss cone at these times. A correction to the calculation using measurements of the trapped flux considerably reduces the discrepancy and provides further support to our hypothesis that weak diffusion leads to underestimates of the EEP.
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DOI：
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作者：
通讯作者：
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影响因子：
5.2
作者：
Seppälä, A;Verronen, PT;Clilverd, MA
通讯作者：
Clilverd, MA
影响因子：
4.4
作者：
Seppala, A.;Lu, H.;Rodger, C. J.
通讯作者：
Rodger, C. J.
太阳质子进入大气的经验确定：对极地飞行路径的影响
影响因子：
3.7
作者：
J. Neal;C. Rodger;J. Green
通讯作者：
J. Green
Riometer-A 电离层吸收连续测量装置
DOI：
10.1109/jrproc.1959.287299
发表时间：
1959
期刊：
Proceedings of the IRE
影响因子：
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作者：
C. Little;H. Leinbach
通讯作者：
H. Leinbach