Goessling Helge F, Rackow Thomas, Jung Thomas
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.
European Centre for Medium-Range Weather Forecasts, Bonn, Germany.
Science. 2025 Jan 3;387(6729):68-73. doi: 10.1126/science.adq7280. Epub 2024 Dec 5.
In 2023, the global mean temperature soared to almost 1.5 kelvin above the preindustrial level, surpassing the previous record by about 0.17 kelvin. Previous best-guess estimates of known drivers, including anthropogenic warming and the El Niño onset, fall short by about 0.2 kelvin in explaining the temperature rise. Using satellite and reanalysis data, we identified a record-low planetary albedo as the primary factor bridging this gap. The decline is apparently caused largely by a reduced low-cloud cover in the northern mid-latitudes and tropics, in continuation of a multiannual trend. Further exploring the low-cloud trend and understanding how much of it is due to internal variability, reduced aerosol concentrations, or a possibly emerging low-cloud feedback will be crucial for assessing the present and expected future warming.
2023年，全球平均气温飙升至比工业化前水平高出近1.5开尔文，比此前纪录高出约0.17开尔文。包括人为变暖和厄尔尼诺现象开始在内的已知驱动因素的先前最佳猜测估计，在解释气温上升方面低了约0.2开尔文。利用卫星和再分析数据，我们确定创纪录的低行星反照率是弥合这一差距的主要因素。这种下降显然主要是由北半球中纬度和热带地区低云覆盖率降低导致的，这是多年趋势的延续。进一步探究低云趋势，并了解其中有多少是由于内部变率、气溶胶浓度降低或可能出现的低云反馈，对于评估当前和未来预期的变暖至关重要。
