The Reuters Climate Monitor is a powerful tool that provides a real-time glimpse into the Earth's temperature anomalies. It's like a thermometer for the planet, showing us where temperatures are unusually hot or cold compared to what was typical in the past. This innovative system is built on a foundation of hourly temperature records from the ERA5 reanalysis dataset, a treasure trove of climate data published by the European Centre for Medium-Range Weather Forecasts' Copernicus program.
What makes this tool truly remarkable is its ability to establish a 'normal' temperature baseline. Climate scientists often refer to this as the 'normal temperature,' and it's calculated using a 30-year window spanning 1961 to 1990. This standard reference period is crucial for understanding climate trends and anomalies. To reduce noise and ensure accuracy, the system uses a 31-day rolling window, considering 15 days on either side of the calendar date across all 30 years of data.
The ERA5 dataset, however, has a slight lag, typically being about five days behind real-time. To address this, the Climate Monitor uses the latest run of the ECMWF medium-range control forecast, formerly known as HRES, which covers the same global grid. This forecast is essential for providing up-to-date comparisons with current conditions.
One of the most fascinating aspects of this tool is its ability to apply a statistical correction. By comparing the control forecast and ERA5 over a multi-year overlap, the system ensures that both datasets are on equal footing. This correction is a testament to the meticulous attention to detail that goes into creating a reliable climate monitoring system.
The Climate Monitor's anomalies are calculated by subtracting the historic norm from today's forecast for each grid square. This results in a map that visually represents how much hotter or colder today's high temperature is compared to the typical high on that date. The tool's regional and country-level averages provide a comprehensive view of temperature anomalies across the globe.
For the United States, the Climate Monitor reports nine climate regions defined by the National Centers for Environmental Information. In Europe, it uses the NUTS-1 statistical regions developed by the European Union. For Asia, it relies on the regions defined by the Intergovernmental Panel on Climate Change's Sixth Assessment Report. This attention to regional detail is crucial for understanding local climate patterns and anomalies.
The development of this tool involved collaboration with over two dozen climate experts, who provided invaluable guidance and advice. Special thanks are due to Alistair Hobday of CSIRO, Lukas Brunner at the University of Hamburg, Claudio Piani at the American University of Paris, and Ed Hawkins at the University of Reading. Their contributions have been instrumental in creating a reliable and informative climate monitoring system.
In conclusion, the Reuters Climate Monitor is a remarkable achievement in climate science, offering a real-time, detailed view of temperature anomalies worldwide. It's a powerful tool for understanding our planet's climate and a testament to the dedication of scientists and researchers in the field.
