The melting of sea ice in the Arctic is well on its way toward its annual "minimum," that time when the floating ice cap covers less of the Arctic Ocean than at any other period during the year. While the ice will continue to shrink until around mid-September, it is unlikely that this year's summer low will break a new record. Still, this year's melt rates are in line with the sustained decline of the Arctic ice cover observed by NASA and other satellites over the last several decades....