Track Zero: Making Two (Cryosphere: Five!) Degrees Real
In Copenhagen in 2009, one of the few victories was a commitment by global leaders to the “two degree goal”: holding the rise in temperature to 2°C (3.8°F) or less globally. A major principle: yet ever since, governments and their climate negotiators have tried unsuccessfully to put this goal into practice as part of a new climate agreement.
The Climate Summit taking place in New York is not a negotiating session, but a gathering of leaders meant to spur those talks forward. As in 2009, the push is on for another principled commitment, this time with a practical goal that all governments can understand and implement: the need for zero net carbon emissions globally by 2050.
The Inter-governmental Panel on Climate Change (IPCC) has categorically stated that we must reach this state of “carbon neutrality,” or even negative emissions by the end of this century to have any chance at all of remaining below two degrees. Substantial work by its Working Groups I, III and others indicates that for a reasonable chance (85%), we must reach zero emissions by 2050.
For such a transition to occur successfully, especially in developing economies this goal must become an integral part of development and infrastructure planning now: a “track zero” that puts human society well on-track for reaching that goal in time. “Track zero” is also something that not only national governments, but also provinces, states, cities, corporations and even individuals can make real. Nor need they wait to meet this goal until 2050: the earlier, the better, especially for the cryosphere.
The “cryosphere imperative” (see IsBlog, April 2014) not only supports the need for “track zero,” it sharpens that need. Two degrees globally means 4-5°C (8-10°F) in the cryosphere. And unlike temperature rise elsewhere, the cryosphere contains an irrefutable threshold of basic physics: cryosphere, and its stabilizing impact on the global climate system disappear when the temperature rises above freezing. It is the one ecosystem where a one-degree difference changes everything.
What happens in the cryosphere then drives the global climate system: through loss of reflective snow, land and sea ice; through sea-level rise from glacier melt; through release of fast-warming methane from permafrost and seabed. More and more research is showing that the cryosphere is crossing critical thresholds even today. Signs of seabed permafrost collapse in Siberia. Loss of entire North American, Andean and Patagonian glacier systems. Perhaps most ominously, essentially irreversible processes already set in motion in West Antarctica, that will lead to the collapse of the West Antarctic ice sheet, meaning that humanity must now prepare for at least three certain meters’ additional sea level rise in coming centuries.
Disruptive as these crossed thresholds are, we face far worse climate triggers that may still be prevented if we act in time. New research into Antarctica’s past, for example shows sea-level rise up to 22 meters (72 feet) at the CO2 levels we are contemplating by the end of this century, crossing into the high-danger zone already at mid-century, absent a “track zero” path. By acting now, we still have time to avoid crossing these other thresholds, which otherwise will simply make the long-term damage greater; and the challenges so very much harder to ourselves, our children and their children.
The front lines of the fight to preserve the global climate system is being fought in the cryosphere now; and it may be won, or lost, well before 2050. “Track zero” must show us the way: yet it is only the beginning.
ICCI Executive Director and Founder Pam Pearson will attend the UN Secretary General’s September 23 Climate Summit in New York, and provide updates from the attempt to make “Track Zero” a mainstream climate commitment there.