Global CO2, a US July peak and European river lows arrived as separate measurements
A global State of the Climate report, a US July temperature peak and European river-flow lows report heat and water at three different measurement scales.
Science··Morning
A global year of greenhouse gases and sea level
The annual State of the Climate report, released as a supplement to the Bulletin of the American Meteorological Society, places the 2025 globally averaged carbon dioxide level at 425.6 parts per million, with an uncertainty of 0.1 parts per million. That figure stands 53 per cent above the preindustrial level of about 278 parts per million. The same global compilation also reports the highest levels yet in global mean sea level and in ocean heat content down to 2,000 metres. Global mean sea level reached about 111.2 millimetres above the 1993 average, when satellite altimetry began, marking the fourteenth consecutive year at a high mark in the satellite series. Fossil fuel emissions are estimated at 10.3 petagrams of carbon per year, with an uncertainty of 0.5, more than three times the earlier level of 3.0 petagrams per year. The 2025 global mean temperature ranked among the three highest in a long instrumental series. The report draws on 625 scientists in 60 countries. These are global annual figures for a single year; they leave national July heat and named river discharge to other instruments.[1]
A national July temperature for the contiguous United States
Separately, the National Oceanic and Atmospheric Administration reported that July 2026 averaged 24.9 degrees Celsius across the contiguous United States, about 1.8 degrees Celsius above the twentieth-century average. The agency says the month finished narrowly ahead of July 1936 and is the warmest month of any kind in a national series spanning 132 years. Heat above normal covered the interior West, the Southwest, the Rockies, the northern Plains, the Upper Midwest and parts of the Gulf Coast and Southeast. Wyoming had its warmest July in its own series, about 2.8 degrees Celsius above its average. July 2012, 2006 and 2022 also sit among the five warmest months in that national series. Outside the United States, regions holding some 900 million people saw their warmest July, among them the Sahel, Central America, France and Spain. NOAA's product is a national monthly temperature average for the lower 48 states. The State of the Climate greenhouse-gas and sea-level compilation is a different dataset, and the NOAA series measures temperature rather than river discharge. The national monthly figure stands beside the global annual report as a second instrument.[2]
River-basin July lows under European monitoring
A third measurement chain sits at river-basin scale. Copernicus data show very low average July flow along 95 per cent of the monitored stretches of the Thames, 85 per cent of the Rhine and about two thirds of the Danube, together with 30 per cent of the Rhone and 40 per cent of the Po. The figures come from the European Flood Awareness System and the European Drought Observatory. They are the weakest July discharge levels since at least 1992, when the flood awareness system began taking such measurements, so the comparison covers a little over three decades rather than the full history of these rivers. The Rhine has sat at the most severe drought level almost continuously since early June, and the Loire showed extremely low flow from the second half of June to the end of July. Western Europe came out of its warmest early summer in the observational series, and the two agencies link the conditions to climate change. Global carbon dioxide, a United States July temperature average and European river-flow lows therefore arrive as three distinct instruments. Each answers a different question of scale.[3]
