The IAGOS-CORE aerosol package: instrument design, operation and performance for continuous measurement aboard in-service aircraft

This work presents the characterisation of the Aerosol Package for the European Research Infrastructure IAGOS (In-service Aircraft for a Global Observing System). Condensation particle counter (CPC) are used to measure the aerosol number concentration of the total and the non-volatile particles. The size distribution is measured by means of an optical particle counter (OPC) in the diameter range of 0.25–3 µm. In particular the OPC is characterised for (1) leakage, (2) flow and calibration stability over the expected IAGOS pressure range of 170 hPa to 1013 hPa, (3) OPC accuracy test by comparing extinction measurements with calculated values from Mie theory using the OPC size distribution and (4) the inter-instrumental precision. The CPC is characterised in the same pressure range for (1) the lower cut-off diameter, (2) the instrument accuracy by comparing with a reference instrument (Faraday Cup Electrometer, FCE) and (3) the instrument precision. We conclude that the IAGOS Aerosol Package is a fully automated, robust, low-maintenance instrument providing high precision measurements with good accuracy

Climatology of NO y in the troposphere and UT/LS from measurements made in MOZAIC

In December 2000, a fully automatic NOy instrument was installed on one of the five Airbus A340 aircraft used in the MOZAIC project (Measurement of Ozone and Water Vapour by Airbus in-service Aircraft) for measurements of O3 and H2O since 1994. This long-range aircraft was operated by Lufthansa, mainly out of Frankfurt and Munich. After an initial testing period, regular data collection started in May 2001. Until May 2005, 1533 flights have been recorded, corresponding to 8500 flight hours of NOy measurements. Concurrent data of NOy and O3 are available from 1433 flights and concurrent data for CO, O3 and NOy exist from 1125 flights since 2002. The paper describes the data availability in terms of geographical, vertical and seasonal distribution and discusses the quality and limitations of the data, including interference by HCN. The vast majority of vertical profiles were measured over Frankfurt, followed by Munich and North American airports. While most of the data were collected in the upper troposphere and lower stratosphere over the North Atlantic, significant data sets exist also from flights to Far and Middle East, whereas data from the tropics and the Southern Hemisphere are relatively sparse

Ein chemisches Aktinometer zur Kalibrierung photoelektrischer Detektoren zur Messung von jNO2_{2}

Zur Kalibrierung von photoelektrischen Detektoren zur Messung der Photolysefrequenz jNO$_{2}$ wurde ein chemisches Aktinometer entwickelt, das auf derzeitaufgelösten spektroskopischen Messung der NO$_{2}$-Konzentration in einem zylindrischen, statischen Reaktor beruht. Das Gerät wurde im Labor getestet und im Juli 1995 für eine Kalibration eingesetzt. Neben einer Beschreibung des Aufbaus und der Durchführung aktinometrischer Messungen steht in diesem Bericht eine ausführliche Analyse möglicher Meßfehler aufgrund reaktionskinetischer und geometischer Faktoren. Die Absolutgenauigkeit aktinometrischer Messungen beträgt demnach 4.5 %. Die Streuung der Messungen vom Juli 1995 liegt bei 4% und könnte wahrscheinlich durch den Einsatz einer stabileren Lichtquelle und einer präziseren Datenaufzeichnung reduziert werden