Unterschiede

Hier werden die Unterschiede zwischen zwei Versionen gezeigt.

Link zu dieser Vergleichsansicht

arbeitsgruppen:lidar:field_experiments [2015/10/29 10:14] (aktuell)
Zeile 1: Zeile 1:
 +===== Field Experiments =====
  
 +As a mobile system our lidar can be easily moved to almost any site. [[:​arbeitsgruppen:​lidar:​prepare|Requirements concerning infrastructure]] are quite small; hardly more than a wall plug is necessary. As a consequence,​ the lidar has been used in several field experiments. Major campaigns include:\\
 +
 +   * **ELITE'​94 ​ (European LITE Correlative Measurement Campaign)** \\ Correlative measurements during the LITE (Lidar In-Space Technology Experiment) flight in September 1994, the first lidar in space, were made at several sites north of Hamburg, Germany. Our system was located in Elpersbüttel.\\ \\
 +
 +   * **OPAP 96/97 (Ozone and particles in photosmog)** \\ Several campaigns of two weeks duration each took place in 1996 and 1997 at rural and urban sites in Bavaria (Germany). They were part of the Bavarian Climate Research Program.\\ \\
 +
 +   * **ACE 2 (Aerosol Characterization Experiment 2)** \\ In June/July 1997, our lidar was transported to Lisboa (Portugal) and installed onboard of a Ukrainian research vessel (Vodyanitski). Measurements were made during five weeks on a cruise between the Portugal coast and Tenerife. [[http://​www.meteo.physik.uni-muenchen.de/​~st212fre/​ace2/​ace2b.htm|More details can be found here.]] \\ \\
 +
 +   * **LACE'​98 (Lindenberger Aerosol Charakterisierungsexperiment)** \\ In July/August 98 in Lindenberg (60 km south east of Berlin) a closure experiment with respect to aerosols and radiation took place. This campaign was also used to compare three out of five lidar systems operated in the AFS-network. After LACE'​98,​ our lidar was moved to Kühlungsborn to include their stationary system in the comparison. \\ \\
 +
 +   * **HAFEX 99 (Hohenpeissenberg Aerosol Formation Experiment)** \\ In April and May 1999, our lidar was operated south of the Hohenpeissenberg (Upper Bavaria). The main purpose was to measure aerosol distributions during strong events of gas to particle conversion in an orographically structured terrain to determine the representativeness of in-situ measurements (aerosol size distribution,​ VOC) in valleys and on top of the Hohenpeissenberg. This experiment was initiated by the German Weather Service. \\ \\
 +
 +   * **SLICE 2000 (Southern Lidar Intercomparison Experiment)** \\ In the framework of the "​European Aerosol Research Lidar Network to Establish an Aerosol Climatology"​ (EARLINET) an instrument comparison for quality assurance was conducted. Our lidar served as a reference system to calibrate the lidars at Thessaloniki and Athens (both in Greece) Lecce, l'​Aquila,​ Potenza and Napoli (all in Italy). For this purpose we did a roundtrip in September and October 2000. The overall agreement between the systems was quite good though smaller deviations occurred due to overlap problems, misalignments and signal-combinations from the analog detection and photon counting regimes, respectively. However, the reasons for any discrepancy could be determined so that SLICE resulted in modifications to all systems. \\ \\
 +
 +   * **Vertikator (Alpine Pumping)** \\ "​Vertikator"​ is an experiment concerning the transport of particles and trace gases from the alpine boundary layer to the free troposphere. Several groundbased station between Munich and Garmisch-Partenkirchen as well as different aircrafts provide detailed measurements for comparison and intialization of mesoscale models. The lidar group participates by providing lidar measurements with the new POLIS system at Lichtenau during July 2002. [[arbeitsgruppen:​lidar:​field_campaigns_polis|Plots of the measurements can be found here]]. \\ \\
 +
 +   * **BBC 2 (Baltex Bridge Campaign)** \\ In May 2003 in Cabauw (The Netherlands) an international experiment to investigate structured boundary layer water clouds, radiation, dynamical processes and their climatic influence was conducted. As the objectives and many participants were the same as those of the BBC campaign (organized by [[http://​www.knmi.nl/​samenw/​cliwa-net/​index.html|CLIWA-NET]],​ [[http://​www.meteo.uni-bonn.de/​projekte/​4d-clouds/​|4D-clouds]],​ [[http://​www.cesar-observatory.nl/​|CESAR]],​ and others) in autumn 2001, the campaign has been named BBC2. The instrumentation consists of a broad range of radiation instruments on the ground and on airplanes; radars, lidars, microwave radiometers,​ in-situ particle probes (aircraft and tethered balloon), and radio sondes. In addition up to three aircrafts were operated. We were asked to participate in BBC2 by the FU-Berlin group of Prof. Jürgen Fischer. Our contribution were high-resolution measurements of the cloud top height with the airborne lidar POLIS onboard the Dornier-228. The Lidar profiles supplemented the CASI and FUBISS measurements of the cloud. \\ \\
 +
 +   * **ICAROS-NET** \\ [[http://​icaros-net.jrc.cec.eu.int/​|ICAROS-NET]] is an EU project and stands for "​Integrated computational assessment of urban air quality via remote observation systems network"​. One of four pilot studies was conducted in the Munich area during May and November 2003. During overpasses of SPOT, Landsat or IRS D1 we provided lidar measurements at our institute and simulataneously at different sites along a west-east cross section through Munich with POLIS. Data gave insight in the spatial homogeneity of the aerosol distribution,​ and thus is a good hint of the representativity of point measurements for validating satellite scenes. \\ \\ 
 +
 +   * **AMMA (African Monsoon Multidisciplinary Analyses)** \\ In the framework of AMMA, POLIS was implemented at the "​supersite"​ in Banizoumbou in Niger. POLIS were operated during January and February in the depolarization mode (355 nm) or the Raman mode (355 nm and 387 nm) to measure vertical profiles of aerosols origninating from biomass burning and Saharan dust outbrakes. Occational measurements were taken at the airport of Niamey to investigate the differences between urban and rural distributions.\\ \\
 +
 +   * **SAMUM (Saharan Mineral Dust Experiment)** \\ The main scientific objective of the SAMUM field campaigns was to provide a radiative closure experiment in the presence of mineral dust close to its source regions and after a few days of transport. For this purpose, remote sensing and in-situ techniques were applied from ground and aircrafts. Furthermore,​ satellite data (e.g., MISR) were considered. \\ In the framework of SAMUM-1 vertical aerosol profiles were measured with MULIS and POLIS at Ouarzazate (Morocco). In addition, our sun- and skyradiometer SSARA was operated. Together with the IfT-lidar a unique instrumentation could be provided: the first time, depolarization at three wavelength was measured simulataneously. Furthermore,​ the complete columnar information could be provided by taking advantage of the different overlaps of the three lidars. SAMUM-2 was conducted at the Cape Verde Islands (Praia). The above mentioned measurement strategy was now applied to dust aerosols (pure as well as mixed with biomass burning aerosols and marine aerosols) transported about one to two thousand kilometers from its source regions. [[http://​samum.tropos.de|More details can be found here.]]