English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

. The Aerosol Robotic Network (AERONET) has provided highlyaccurate, ground-truth measurements of the aerosol optical depth (AOD) usingCimel Electronique Sun–sky radiometers for more than 25 years. In Version 2 (V2)of the AERONET database, the near-real-time AOD was semiautomaticallyquality controlled utilizing mainly cloud-screening methodology, whileadditional AOD data contaminated by clouds or affected by instrumentanomalies were removed manually before attaining quality-assured status(Level 2.0). The large growth in the number of AERONET sites over the past25 years resulted in significant burden to the manual quality control of millionsof measurements in a consistent manner. The AERONET Version 3 (V3) algorithmprovides fully automatic cloud screening and instrument anomaly qualitycontrols. All of these new algorithm updates apply to near-real-time data aswell as post-field-deployment processed data, and AERONET reprocessed thedatabase in 2018. A full algorithm redevelopment provided the opportunity toimprove data inputs and corrections such as unique filter-specifictemperature characterizations for all visible and near-infrared wavelengths,updated gaseous and water vapor absorption coefficients, and ancillary datasets. The Level 2.0 AOD quality-assured data set is now available within amonth after post-field calibration, reducing the lag time from up to severalmonths. Near-real-time estimated uncertainty is determined using dataqualified as V3 Level 2.0 AOD and considering the difference between the AODcomputed with the pre-field calibration and AOD computed with pre-field andpost-field calibration. This assessment provides a near-real-timeuncertainty estimate for which average differences of AOD suggest a +0.02  biasand one sigma uncertainty of 0.02, spectrally, but the bias and uncertaintycan be significantly larger for specific instrument deployments. Long-termmonthly averages analyzed for the entire V3 and V2 databases producedaverage differences (V3–V2) of  + 0.002 with a ± 0.02 SD (standarddeviation), yet monthly averages calculated using time-matched observationsin both databases were analyzed to compute an average difference of  −0.002 with a ±0.004  SD. The high statistical agreement inmultiyear monthly averaged AOD validates the advanced automatic dataquality control algorithms and suggests that migrating research to theV3 database will corroborate most V2 research conclusions and likely lead tomore accurate results in some cases.

atmospheric measurement techniques

Advancements in the Aerosol Robotic Network (AERONET) Version 3 database – automated near-real-time quality control algorithm with improved cloud screening for Sun photometer aerosol optical depth (AOD) measurements