Nitrogen dioxide reductions from satellite and surface observations during COVID-19 mitigation in Rome (Italy).

Lockdown restrictions were implemented in Italy from 10 March 2020 to contain the COVID-19 pandemic. Our study aims to evaluate air pollution changes, with focus on nitrogen dioxide (NO), before and during the lockdown in Rome and in the surroundings. Significant NO declines were observed during the COVID-19 pandemic with reductions of - 50%, - 34%, and - 20% at urban traffic, urban background, and rural background stations, respectively.

Aerosol optical retrieval and surface reflectance from airborne remote sensing data over land.

Quantitative analysis of atmospheric optical properties and surface reflectance can be performed by applying radiative transfer theory in the Atmosphere-Earth coupled system, for the atmospheric correction of hyperspectral remote sensing data. This paper describes a new physically-based algorithm to retrieve the aerosol optical thickness at 550 nm (τ(550)) and the surface reflectance (ρ) from airborne acquired data in the atmospheric window of the Visible and Near-Infrared (VNIR) range. The algorithm is realized in two modules.

Performance of a FieldSpec spectroradiometer for aerosol optical depth retrieval: method and preliminary results.

The performance of a FieldSpec spectroradiometer for retrieving aerosol optical depth (AOD) has been assessed after modifying its basic configuration in order to measure direct solar irradiance at ground level. The FieldSpec measurements were obtained during four summertime days in the years 2004 and 2005, over a Spanish agricultural site in Barrax, Albacete (30 degrees 3(') N, 2 degrees 6(') W, 700 m a.s.

Road Asphalt Pavements Analyzed by Airborne Thermal Remote Sensing: Preliminary Results of the Venice Highway.

This paper describes a fast procedure for evaluating asphalt pavement surface defects using airborne emissivity data. To develop this procedure, we used airborne multispectral emissivity data covering an urban test area close to Venice (Italy).For this study, we first identify and select the roads' asphalt pavements on Multispectral Infrared Visible Imaging Spectrometer (MIVIS) imagery using a segmentation procedure.