Differential Optical Absorption Spektoscopy (DOAS) Observations from HALO

在SPP-1294的第一阶段，设计和组装两台新型DOAS（差分光学吸收光谱）仪器，简称HALO mini-DOAS和2-D成像DOAS （2-D I-DOAS）光谱仪，用于未来部署在HALO飞机上。目前（2009年底），这两种仪器都在等待参与即将到来的测试任务和科学任务的最终飞机认证。预计对HALO上的仪器的测试将在仍在进行的项目结束（2010年底）之前完成。随后的项目将专门用于科学应用，即实际利用开发和建造这两种仪器的投资。这两个分光计设计用于监测1-D和/或2-D时空图，垂直剖面，和/或柱量的一套大气微量气体（如，O3, NO2, CH2O, C2O2H2, BrO, OClO， IO， OIO, O4, O2, H2O）和云参数（如，气体，液体和固体水含量，云光学厚度）。由于这两种仪器可以观测到广泛的重要大气参数（其中一些最近的例子在下文中提供），这两种仪器中的任何一种或两种都被邀请参加即将到来的HALO测试任务和科学任务（例如，TACTS, TACTS/SALSA, CIRRUS-ML, CIRRUS-RS， OMO， POLSTRACC, HALO- eo, EU-SHIVA, SHIVA/ nox - hox - ox， NARVAL和ACRIDION）。然而，要充分利用测量到的现场数据，例如，从测量到的倾斜柱数量推断浓度分布，将需要进一步的评估步骤。这些步骤将涉及利用复杂的辐射传递计算和数学反演技术对光谱测量进行解释，这些技术受限于光化学、微物理或动态建模的输出，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.