Justino Martínez¹, Carolina Gabarró¹, Veronica Gonzalez-Gambau¹, Cristina González-Haro¹, Estrella Olmedo¹, Joaquim Ballabrera-Poy², Antonio Turiel¹, Rafael Catany³, Manuel Arias³, Rhiannon Davies³, Laurent Bertino⁴, Jiping Xie⁴, Roshin P. Raj⁴, Roberto Sabia⁵, Wenqing Tang⁶, Simon H Yueh⁶ and Arctic+ project: team and collaborators, (1)Barcelona Expert Center, Institute of Marine Sciences, CSIC, Physical and Technological Oceanography, Barcelona, Spain, (2)Institute of Marine Sciences, CSIC, Physical and Technological Oceanography, Barcelona, Spain, (3)Argans Ltd., Plymouth, United Kingdom, (4)Nansen Environmental and Remote Sensing Center, Bergen, Norway, (5)Telespazio-Vega for European Space Agency, Frascati, Italy, (6)Jet Propulsion Laboratory, Pasadena, CA, United States