The Extreme Summer Heat of 2025 Is the Result of Constructive Interference among the Dominant Teleconnection Modes

The summer of 2025 featured unprecedented extreme heat across western and northern Europe, East Asia, the Middle East, and parts of central Africa. This synchronized heatwave cannot be attributed to a single teleconnection pattern, but is instead explained by concurrence of multiple dynamical modes. Using a set of Green’s function q-flux perturbation experiments, we construct the corresponding linear response function (LRF), provide an attribution and reconstruction of the 2025 heatwave, and identify the dominant remote oceanic forcings. The observed temperature and upper-level circulation anomalies are well represented by a linear combination of the three leading neutral modes, with these modes explaining approximately 74.1% of the variance. The dynamical modes derived from the Green’s function framework can be mapped onto previously identified modes in the observations: mode 1 aligns with the Trans-Eurasian heatwave-drought train (TEHD) pattern. Mode 2 exhibits a composite structure that includes signals of the positive phase of the Pacific-Japan (PJ) pattern. Mode 3 is closely associated with the circumglobal teleconnection (CGT) wave train. The q-flux reconstructed from the three leading modes shows cooling in the eastern tropical Pacific and warming in the mid- to high-latitude oceans, consistent with the reconstructed sea surface temperature (SST) pattern and the observed summer anomalies of 2025, highlighting the role of oceanic thermal forcing, particularly in the extratropics, in shaping the atmospheric response.