Development of an Instrument for Multispectral Measurement of Aerosol Light Absorption

这是一项重大研究仪器奖，旨在支持开发一种仪器，用于测量太阳光谱中不同波长的气溶胶颗粒的吸收。 气溶胶吸收和散射太阳辐射，从而影响区域和全球气候。 虽然缺乏关于气溶胶吸收光谱的准确数据，但现有证据表明，来自不同来源的气溶胶具有明显不同的光谱。 例如，撒哈拉的尘埃似乎强烈吸收紫外线，但在光谱的可见光部分吸收较弱。 另一方面，柴油机烟灰在光谱上吸收更均匀。 到目前为止，还没有仪器可以测量气溶胶在两个以上波长的原位吸收，尽管辐射传输计算所需要的是吸收光谱的详细表示。 因此，将建立一个多波长的单元，基于共振光声原理，以测量在六个波长的吸收跨越光谱从紫外到红外。 通过测量760 nm氧气A波段的（已知）吸收来建立校准。 该仪器将用于测量不同种类的自然和人为气溶胶的光谱吸收。 这些信息对于了解人类使用燃烧对气候的影响至关重要。

This is a Major Research Instrumentation award to support the development of an instrument for measuring the absorption of aerosol particles at different wavelengths in the solar spectrum. Aerosols absorb and scatter solar radiation and thus influence regional and global climate. Though accurate data on aerosol absorption spectra are lacking, the available evidence indicates that aerosols from different sources have markedly different spectra. For example, Saharan dust appears to absorb strongly in the ultraviolet but weakly in the visible part of the spectrum. Diesel soot, on the other hand, absorbs more uniformly over the spectrum. To now, no instrument has been available to measure the in-situ absorption of aerosols at more than two wavelengths, though what is needed for radiative transfer calculations is a detailed representation of the absorption spectrum. Accordingly, a multi-wavelength unit will be built, based on the resonant photoacoustic principle, to measure the absorption at six wavelengths spanning the spectrum from the ultraviolet to the infrared. Calibration is established by measuring the (known) absorption of the 760-nm oxygen A-band. The instrument will be employed for measurements of the spectral absorption of different kinds of natural and anthropogenic aerosols. This information is essential for understanding the consequences of the human use of combustion on climate.