(a) A schematic of the newly reconfigured HWV instrument that includes both the Lyman-α and HHH detection axes. The subsystems that measure temperature and pressure and control the sampling and velocity through the instrument duct are labeled. (b) The HWV instrument loaded in the spearpod of the WB-57 during the MACPEX mission. (c) The primary inlet and HHH detection axis.
Diagram of HHH optical components. (a) Laser pressure vessel (LPV). (b) Signal pressure vessel (SPV).
Diagram of the electronics used to process the detector signals including the anti-alias filter (AAF) and Scalable Signal Processing (SSP) board. LVDS: Low Voltage Differential Signaling; SPI: Small Peripheral Interface; DSP: Digital Signal Processing; PHY: Ethernet Physical Layer Transceiver; FPGA: Field Programmable Gate Array.
(a) A typical set of HHH spectra acquired in flight on 4/20/11 at 160 hPa, −45 °C, and 4.3 ppmv H2O. The spectra have been normalized to the voltage of the Herriott cell spectrum. (b) The same data as in (a), now de-trended from the baseline power curve and fit using a voigt lineshape. The top panel shows the residual between the raw and fit data.
Schematic of HWV calibration bench. Controlled quantities of saturated air are combined with a flow of dry air which is directed to both the HHH and Lyman-α detection axes.
(a) Laboratory intercomparison between Lyman-α, HHH, and the bubbler, where the bubbler data includes the water added by the bubbler plus the residual water vapor in the “dry” air flow as measured by Lyman-α. (b) H2O as measured by HHH compared to that measured by Lyman-α for the laboratory calibration shown to the left.
Sample time series of Lyman-α and HHH water vapor measurements from the flight on April 25, 2011 during the first high altitude leg.
(a) H2O as measured by HHH compared to that measured by Lyman-α for each day that HHH acquired data. Also shown is a 1:1 fit with a +0.35 ppmv offset and ±10% bounds. (b) The fractional difference between HHH and Lyman-α for each flight day is shown vs. Lyman-α water vapor.
TDL water vapor instruments which have been flown in the UT/LS.
Article metrics loading...
Full text loading...