In this week’s newsletter: The melting of the Arctic’s summer sea ice is the most visible upshot of the climate crisis. Refreezing it might be a long shot – but do drastic times call for drastic measures? • Don’t get Down to Earth delivered to your inbox? Sign up here In this week’s newsletter: The melting of the Arctic’s summer sea ice is the most visible upshot of the climate crisis. Refreezing it might be a long shot – but do drastic times call for drastic measures? Don’t get Down to Earth