The phrase "spring sea" refers to the ocean or sea during the season of spring. It implies a sense of freshness, renewal, and potential growth as spring is a time when new life emerges after winter. Full definition
This good agreement between projections and observations is consistent with the conclusion that initial conditions of spring sea ice are often an important factor in determining ice development over the course of the summer. (searcharcticscience.org)
That's important, she said, because cloud cover influences when in spring sea ice begins melting. (scientificamerican.com)
The publicly available report also divides the Arctic Ocean into 12 regions, and calculates the changes in the dates of spring sea ice retreat and fall freeze - up from NASA satellite images taken between 1979 and 2013. (sciencedaily.com)