Differential Optical Absorption Spektoscopy (DOAS) Observations from HALO

在SPP-1294的第一阶段，为未来在Halo飞机上部署提供资金，设计和组装了两个新的DOAS(差分光学吸收光谱分析)仪器--简称Halo Mini-DOAS和2-D成像DOAS(2-D I-DOAS)光谱仪。目前(2009年底)，这两项仪器都在等待参加即将到来的试验飞行任务和科学飞行任务的最后飞机认证。预期在仍在进行中的项目(2010年底)结束之前，将完成对Halo上仪器的测试。随后的项目将致力于科学应用，即实际利用开发和建造这两个仪器的投资。这两个光学光谱仪被设计成监测一维和/或二维空间和时间图、垂直剖面和/或一组大气痕量气体(例如，O3、NO2、CH2O、C2O2H2、BrO、OClO、IO、OIO、O4、O2、H2O)和云参数(例如，气态、液态和固态水含量、云的光学厚度)。由于两台仪器可用来观测的重要大气参数范围很广(下面的报告列举了其中一些最近的例子)，请两台仪器中的一台或两台都参加即将进行的HALO测试飞行任务和科学飞行任务(例如TACTS、TACTS/SALSA、CERRUS-ML、CERRUS-RS、OMO、POLSTRAC、HALO-EO、EU-SHIVA、SHIVA/NOX-HOX-XOX、NARVAL和ACRIDION)。然而，充分利用测量的现场数据，例如从测量的斜柱量推断浓度分布，将需要进一步的评估步骤。这些步骤将涉及用复杂的辐射传输计算与数学反演技术相结合来解释光谱测量，这些技术受光化学、微物理或动力学模拟的输出的约束，具体取决于应用。

Within the first stage of SPP-1294, the design and assembly of two novel DOAS (Differential Optical Absorption Spectrometry) instruments – briefly called HALO mini-DOAS and 2-D imaging DOAS (2-D I-DOAS) spectrometer- were funded for future deployments on the HALO aircraft. At present (late 2009) both instruments await final aircraft certification for participating in upcoming test missions and scientific missions. It is expected that testing of the instruments on HALO will be accomplished before the end of the still ongoing project (late 2010). The follow-on project will then be devoted to scientific applications i.e. to actually making use of the investment of developing and building the two instruments. The two optical spectrometers are design to monitor 1-D and/or 2-D spatial and temporal maps, vertical profiles, and/or column amounts of a suite of atmospheric trace gases (e.g., O3, NO2, CH2O, C2O2H2, BrO, OClO, IO, OIO, O4, O2, H2O) and cloud parameters (e.g., gaseous, liquid, and solid water contents, cloud optical thickness). Due to the wide range of important atmospheric parameters accessible for observation with the two instruments (of which some recent examples are given in the report below) either of the two instruments or both are invited to participate in the upcoming HALO test missions and scientific missions (e.g., TACTS, TACTS/SALSA, CIRRUS-ML, CIRRUS-RS, OMO, POLSTRACC, HALO-EO, EU-SHIVA, SHIVA/NOX-HOX-XOX, NARVAL, and ACRIDION). A full exploitation of the measured field data, e.g., to infer concentration profiles from the measured slant column amounts, however will require further evaluation steps. These steps will involve the interpretation of the spectroscopic measurements with sophisticated radiative transfer calculations in combination with mathematical inversion techniques, which are constraint by outputs of photochemical, microphysical, or dynamical modeling depending on the application.