Fig. 4. Heat balance change over Arctic shelf regions caused by influx of riverine heat.

Mean annual energy budget, including heat sources and sinks over the six Arctic shelf regions (Fig. 1). The heat sources are constituted by influx of riverine heat (Q_rh) and additional absorption of solar radiation at the ocean surface caused by the sea ice–albedo feedback (Q_sw). The heat sinks are formed by ocean warming (Q_ow), sea ice melting (Q_im), and heat release from ocean to atmosphere (Q_ao). All values are averaged for the 1980–2015 period. The vertical lines at the top of the bars represent uncertainties of the estimates, defined by the three sensitivity experiments (Supplementary Materials).