Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: aerosol extinction

Sortuj według:

Ogranicz wyniki do:

Study of vertical structure of aerosol optical properties with sun photometers and ceilometer during the MACRON campaign in 2007

Markowicz K., Zieliński T., Blindheim S., Gausa M., Jagodnicka A., Kardas A., Kumala W., Malinowski S., Petelski T., Posyniak M.

Acta Geophysica

2012

Vol. 60, no. 5

1308-1337

This paper presents the measurements of a vertical structure of aerosol optical properties performed during the MACRON (Maritime Aerosol, Clouds and Radiation Observation in Norway) campaign, which took place in July and August 2007 at ALOMAR observatory on And?ya island (69.279 °N, 16.009 °E, elevation 380 m a.s.l.). The mean value of the aerosol optical thickness (AOT) at 500 nm during campaign was 0.12. Significant increase of the AOT above longtime mean value was observed on 7 and 8 August 2007 when the AOT exceeded 0.4 at 500 nm. Analyses of back trajectories show the aerosol transported from over Africa and Central Europe. The aerosol extinction coefficient obtained from the synergy of ceilometer and sun photometer observations reached 0.05-0.08 km-1 (at 1064 nm) in the dust layer. The single scattering albedo at the ALOMAR observatory decreased during the dust episode to 0.93-0.94, which indicates some absorptive aerosols in the lower PBL.

Continuous wave laser celiometer with code modulation for measurements of cloud base height

Holejko K., Nowak R.

Opto-Electronics Review

2000

Vol. 8, No. 2

195-199

This paper presents a CW low power celiometer designed for cloud base height measurements. The 500-mW CW IR laser of the celiometer is modulated by a pseudo noise sequence. The scattered and delayed light signal is obtained by a correlation system with output bandwidth of only 3.5 Hz. This enables to obtain the ranges of 1.2 km to the clouds and the accurancy of the order of ± 2.5 m to the solid objects. The following problems are discussed: principle of operation, device architecture, and error estimation. Some measurement results are also enclosed.