Ground‐based stations are one of many observing systems contributing to the generation of data to evaluate climate trends and variations locally and globally. Networks of stations are made of various numbers of observing sites, equipped with different typologies and varieties of instruments, differently managed and maintained. Among such networks a limited number of stations are required as a reference, to provide top quality...

A maximum temperature of 48.8°C (119.8°F) was purportedly recorded for the automated station in Siracusa (Syracuse) Contrada Monasteri, on the island of Sicilia (Sicily) Italy on August 11, 2021. A World Meteorological Organization (WMO) ad hoc evaluation committee was assembled to assess the possibility that the Sicilia temperature was the highest recorded temperature in WMO Region VI (continental only). After a detailed revi...

Monitoring the state of oceans and their evolution in space and time is of fundamental importance as they are severely impacted by climate change, showing an increase in temperature, acidity and stratification. The role of metrology in the marine sector is relevant for helping oceanographers consolidate measurement approaches already in place by introducing concepts like metrological traceability and measurement uncertainty. T...

With the purpose of revising World Meteorological Organization's Commission for Instruments and Methods of Observation (WMO/CIMO) Guide #8 on weather stations siting, an experiment to evaluate metrologically the maximum influence of a paved road on 2‐m air temperature measurements (“road siting effect”) has been designed, installed and run in Italy. It consists of a 100‐m long array of seven measurement stations, at increasing...

Rockfalls are one of the most common instability processes in high mountains. They represent a relevant issue, both for the risks they represent for (infra) structures and frequentation, and for their potential role as terrestrial indicators of climate change. This study aims to contribute to the growing topic of the relationship between climate change and slope instability at the basin scale. The selected study area is the Be...

A World Meteorological Organization (WMO) committee officially evaluated temperature record extremes of 54.0°C at two locations, one in Mitribah, Kuwait on July 21, 2016 and a second in Turbat, Pakistan on May 28, 2017. The committee agreed that quantity and quality of documentation of both observations were excellent. Additional metrological testing of the equipment focused on three aspects: the calibration of both thermomete...