COVID-19 ISO Insights

How the COVID-19 Crisis May Affect Weather Data

April 20, 2020

By: Christopher Sirota, CPCU

During the COVID-19 crisis, experts (including Verisk's AIR) have been forecasting the geographic spread of the virus and the number of hospitalizations from this unfortunate event. Strangely, the COVID-19 crisis itself may be affecting the quality of data used for a more familiar forecast: the weather.

Commercial Airlines Also Provide Weather Measurements

There have been reports, such as one from Forbes in 2019, indicating how current and upcoming 5G networks might interfere with weather data, specifically measurements of water vapor data in the atmosphere. In that article, Forbes noted that although about 90% of the data used in weather modeling comes from polar orbiting satellites, forecasts are typically developed using data from weather balloons, aircraft, satellites, and numerous ground instruments to provide an initial "assessment" of the three-dimensional atmosphere. That data is fed into complex computer models solving fluid dynamics, thermodynamics, and physics equations on a rotating globe at several different levels.

One of those aforementioned data sources, aircraft, has reportedly been affected by the COVID-19 crisis. According to a Forbes article, the global commercial airline fleet is expected to drop in size by 20% by the end of May 2020, with capacity dropping by 60% by the end of April.

Given this, the World Meteorological Organization (WMO) states that they are concerned about the reduced number of weather data observations that is resulting from this global reduction of commercial airline flights.

Per the article, although most weather data, as noted above, is sourced from satellites, commercial airlines provide daily:

[i]n-flight measurements of ambient temperature and wind speed and direction [which] are a very important source of information for both weather prediction and climate monitoring. Commercial airliners contribute to the Aircraft Meteorological Data Relay programme (AMDAR), which uses onboard sensors, computers and communications systems to collect, process, format and transmit meteorological observations to ground stations via satellite or radio links […] The AMDAR observing system has traditionally produced over 700 000 high-quality observations per day of air temperature and wind speed and direction, together with the required positional and temporal information, and with an increasing number of humidity and turbulence measurements being made.

Thus, the reduction in commercial air traffic has reportedly caused a significant decrease in the amount of daily AMDAR data. In the near term, the WMO reportedly expects the initial impact of such a decrease in data to have a “modest” effect on most forecasts; however, reliability in the long term may gradually worsen.