Description: Publication date: Available online 15 June 2018 Source: Polar Science Author(s): Yushiro Tsukada, Hiromichi Ueno, Naoki Ohta, Motoyo Itoh, Eiji Watanabe, Takashi Kikuchi, Shigeto Nishino, Kohei Mizobata Solar heating in summer in the Chukchi Sea was estimated using satellite-derived sea-ice concentration data and reanalysis shortwave radiation data. The shortwave radiation was validated by in-situ data obtained by the R/V Mirai and NCEP-CFSR/CFSv2 was found to reproduce in-situ data accurately compared with NCEP/NCAR Reanalysis 1 and ERA-Interim. Solar heating integrated over the Chukchi Sea in summer varied interannually from 3.6 × 10 20  J in 2000 to 6.7 × 10 20  J in 2015, and was up to twice the northward heat flux through the Bering Strait. The total heating in the Chukchi Sea implies that the heat in the Chukchi Sea provided by northward heat flux through the Bering Strait is amplified by solar heating in the Chukchi Sea. We further compared these heat fluxes into the Chukchi Sea with the summertime northward heat flux through Barrow Canyon, an indicator of heat flux from the Chukchi Sea to the Arctic basin. The northward heat flux through Barrow Canyon was affected by the interannual variation of solar heating in the eastern Chukchi Sea. These results imply that modification of Pacific water in the Chukchi Sea by solar heating plays an important role in the interannual variation in heat transport from the Chukchi Sea to the western Arctic basin.