We compared six years of carbon dioxide and methane measurements from two nearby laboratories at the high mountain station on Mount Cimone, Italy. Both recorded similar long-term and seasonal changes, but hourly readings often differed beyond limits recommended by WMO. Sampling location, data selection and moisture removal contributed to these differences; human presence may also have played a role. Standardization of sampling and procedures can make greenhouse gas measurements more consistent.

Coastal cities face growing flood risk from rising seas and storms. Scientists estimate dangerous water levels using satellite measurements of sea level and computer models of ocean behaviour, but the two are often combined inconsistently. We reviewed this research and found the real challenge is not merging the data, but making sure both methods measure the same thing, the same way. Solving this could lead to more reliable, consistent flood-risk estimates for coastal communities worldwide.