A Review of Operational Ensemble Forecasting Efforts in the United States Air Force

Evan L Kuchera,Glenn A Creighton,Steven A Rugg,Scott A Rentschler

doi:10.3390/atmos12060677

Abstract

United States Air Force (USAF) operations are greatly influenced and impacted by environmental conditions. Since 2004, USAF has researched, developed, operationalized, and refined numerical weather prediction ensembles to provide improved environmental information for mission success and safety. This article reviews how and why USAF capabilities evolved in the context of USAF requirements and limitations. The convergence of time-lagged convection-allowing ensembles with inline diagnostics, algorithms to estimate the sub-grid scale uncertainty of critical forecasting variables, and the distillation of large quantities of ensemble information into decision-relevant products has led to the acceptance of probabilistic environmental forecast information and widespread reliance on ensembles in USAF operations worldwide.

Highlights

The combination of improved diversity in initial conditions (ICs), convection-allowing resolution, and reliable algorithms tailored to mission impacts resulted in a regional ensemble capability that was well-received by users, and showed useful skill across many variables
Surveys and webpage product analyses were performed in 2016 [99] and 2020. 100 surveys were completed from August to October 2020, with users reporting that 89% of supported missions wanted a combination of “yes/no” and “confidence” information, that the 4-km Mesoscale Ensemble Prediction Suite (MEPS) was a more critical forecasting tool than the 20-km MEPS or Global Ensemble Prediction Suite (GEPS)
For the first 6 months of 2020, 6020 unique users who authenticated into the United States Air Force (USAF) website used an ensemble product, with 87.8 million overall product downloads

Summary

Introduction

Review of Operational EnsembleWeather impacts United States Air Force (USAF) operations worldwide, both via threats posed to life and property and via advantages conferred (with superior understanding compared to an adversary) in the sphere of conflict.The canonical example of the latter is the D-Day invasion [1] in June 1944 duringWWII, when in the midst of an overall stormy pattern that led Nazi leaders in Europe to let down their guard, Allied forecasters found a brief window of adequate weather for attack.The Allies both reduced risks to property and safety and improved their likelihood of mission success by exploiting the opportunities gained from superior weather information.An example of failure occurred during Operation Eagle Claw in April 1980 [2] when mission planners and meteorologists did not anticipate and account for convectivelygenerated dust storms that could not be seen by the satellites of that era. Weather impacts United States Air Force (USAF) operations worldwide, both via threats posed to life and property and via advantages conferred (with superior understanding compared to an adversary) in the sphere of conflict. The canonical example of the latter is the D-Day invasion [1] in June 1944 during. The Allies both reduced risks to property and safety and improved their likelihood of mission success by exploiting the opportunities gained from superior weather information. An example of failure occurred during Operation Eagle Claw in April 1980 [2] when mission planners and meteorologists did not anticipate and account for convectivelygenerated dust storms that could not be seen by the satellites of that era. An unpublished study of 266 major battles from 1479 BC to 2003 AD [4] found that weather was a factor in the outcome of 36% of them, evidence that the D-Day and Operation The zero visibility conditions were the primary factor that led to the mission being aborted, indirectly led to eight fatalities when a helicopter later crashed into a transport aircraft, and arguably cost a US President his re-election bid [3].

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Results

Conclusion