ARL Weekly News – November 6, 2020

Recent Events

Improvements to HYSPLIT User Interface

Several usability improvements to HYSPLIT have been incorporated per user feedback. A ring radius and its center position can be specified through input fields. The location search now allows different view points, including the ability to enter a street address directly. A satellite view (with an option for MODIS/VIIRS satellite imagery) is also available to identify industrial structures and equipment more accurately. New user controls include “map,” “zoom,” “download,” “play,” and “stop” labels on the interactive map for clarity. These user interface changes are available at the ARL development site: Also in progress is a cloud option that is being tested by NOAA Web Operation Center (WOC) and ARL.

These improvements expand on the ability to use HYSPLIT simulations to enable precise and quick reaction by local response agencies. Interest in applying HYSPLIT to more short-range problems increased following 9/11 with a request by the National Weather Service for routine HYSPLIT forecasts at a number of fixed locations.  An on-demand, web hosted capability hosted at NOAA’s 24/7 Web Operations Center was established to replace a cumbersome and a dedicated system for Weather Forecast Office (WFO).  This interface, developed in collaboration with the National Ocean Service’s Office of Response and Restoration, links HYSPLIT with a chemical database permitting the WFO to select a realistic emission scenario and create output graphics linked with human exposure guidelines.

The Weather Forecast Office at Houston/Galveston Texas had initiated these particular usability changes and replied with the following message: “Kudos to your entire team! Your timeliness, communication, and willingness to take NWS field office input is VERY much appreciated. Cannot thank you enough!” Developer Sonny Zinn was responsible for implementing these changes and thanks to him for providing such superior customer service with respect to HYSPLIT.


HRRR Archive database updates

ARL’s HRRR archive data since June 12, 2019, which was a concatenation of zero-hour HRRR forecasts, has been replaced by a concatenation of one-hour forecasts, and will continue into the future. Files are at It was discovered that vertical velocity at the zero-hour was incorrect, and in particular this was noticed over water. HRRR developers at OAR Global Systems Laboratory recommended replacing the zero-hour for all fields with the one-hour forecast. Users needing to compare differences between the zero-hour and one-hour forecast archives will find the legacy files are available at the ftp server in the directory named “hrrr.v2”.


Special Issue: Biosphere-Atmosphere Interactions with Remote Sensing

Praveena Krishnan is a guest editor for a special issue of Remote Sensing titled “Understanding Biosphere-Atmosphere Interactions with Remote Sensing.” Manuscripts are solicited from original research that synthesizes and advances our understanding of the energy, water, carbon, and trace gas exchange processes, drivers, coupling, interactions, teleconnections, and feedbacks in the biosphere-atmosphere interface across all spatial and temporal scales. Contributions dealing with remote sensing technologies and applications of passive or active sensors onboard any platforms including ground/airborne/UAV/satellite or its combinations with modeling efforts or reanalysis are welcome and due 12/31/2021. More details are available online.