page_title: Differential optical absorption spectroscopy
hierarchical_section_title: Differential optical absorption spectroscopy
caption_attribution_description: English: Telescope of Longpath DOAS Measurements on Cape Verde Atmospheric Observatory, Sao Vicente, Cape Verde, during HaLoCaVe Campaign 2010
context_page_description: In atmospheric chemistry, differential optical absorption spectroscopy is used to measure concentrations of trace gases. When combined with basic optical spectrometers such as prisms or diffraction gratings and automated, ground-based observation platforms, what we have is a cheap and powerful means for the measurement of such trace gas species as ozone and nitrogen dioxide. Typical setups allow for detection limits corresponding to optical depths of 0.0001 along lightpaths of up to typically 15 km and thus allow for the detection also of weak absorbers, such as water vapour, Nitrous acid, Formaldehyde, Tetraoxygen, Iodine oxide, Bromine oxide and Chlorine oxide.
context_section_description: In atmospheric chemistry, differential optical absorption spectroscopy (DOAS) is used to measure concentrations of trace gases. When combined with basic optical spectrometers such as prisms or diffraction gratings and automated, ground-based observation platforms, what we have is a cheap and powerful means for the measurement of such trace gas species as ozone and nitrogen dioxide. Typical setups allow for detection limits corresponding to optical depths of 0.0001 along lightpaths of up to typically 15 km and thus allow for the detection also of weak absorbers, such as water vapour, Nitrous acid, Formaldehyde, Tetraoxygen, Iodine oxide, Bromine oxide and Chlorine oxide.
caption: Long-path DOAS System at the Cape Verde Atmospheric Observatory (CVAO) at São Vicente, Cape Verde
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