All posts by Sean Ahearn

Esri Blog on 9/11 Response and Recovery

Check out Esri’s Blog on “A Look Back: How a GIS Team Guided Response and Recovery After 9/11” published on September 10, 2021 by Ryan Lanclos and David LaShell.

Two decades ago, cutting-edge geospatial tools were deployed by professionals in the response and recovery efforts following the 9/11 terrorist attacks, and lessons learned are still guiding software advancements.

Key Takeaways

  • Mapping teams provided critical insight in response to the 9/11 attacks in New York City.
  • Experts in the geographic approach created new tools—and new ways of using old ones—to guide relief efforts.
  • City agencies quickly shared data, building on the highly detailed NYCMAP basemap, to address crises and solve problems.

Excerpt taken from

CARSI Covid-19 model

The CARSI (Center for Advanced Research of Spatial Information) Model uses an embedded recursive SIR (suseptable, infected, removed) model to simultaneously solve for two key epidemiological parameters Ro and the contact ratio (CR). Modeling performed by Sean C. Ahearn, Professor & Director, Web-mapping by Shipeng Sun, Assistant Professor, View the CARSI Covid-19 model at

Ahearn presented at NAS Workshop on Geospatial Needs for a Pandemic-Resilient World

Professor Sean C. Ahearn participated in the “Geospatial Needs for a Pandemic-Resilient World_Agenda” June 17, 2020, hosted by the National Academies of Science

His presentation, “An embedded recursive SIR model for county level analysis of COVID-19” included

  • predictions of death rates for the next 2 months for the US as a graph
  • Ro & Contact ratio (i.e. diffusion) parameter estimation for every county in the US as a “map”
  • predictive model for every county in the US

Ahearn at 2017 NY Solar Summit

Solar (+Storage) on NY’s 21st Century Grid
John Jay College, City University of New York, Manhattan
JUNE 21, 2017

2017 solar summit banner

Sustainable CUNY’s 11th annual NY Solar+Storage Summit will take place on June 21, 2017 at John Jay College. We will be announcing our new solar map for Long Island at the Summit. Anyone living on Long Island, the Five Boroughs or Westchester can now just put in their address and get their solar potential ( ).

Visit the Solar Summit website and register today!