By by Roberta Harrington in Los Angeles Concentrations of CO2, methane and nitrous oxide climbed to record levels in the global atmosphere in 2023, contributing ever more to the climate crisis. This is according to scientists from the US National Oceanic and Atmospheric Administration (NOAA). The rise in these gases, as detected in air samples by NOAA’s Global Monitoring Laboratory (GML) last year, didn’t reach the record surges seen in recent times. Nonetheless, they mirrored the steep inclines observed over the past decade. “NOAA’s long-term air sampling programme is essential for tracking c…