From “Life After Doom: Wisdom and Courage for a World Falling Apart” by Brian D. McLaren
Now imagine that we get our act together and stop adding carbon to the atmosphere tomorrow, so we stop trapping solar heat within the blanket of our atmosphere and we reach “net zero” emissions by this weekend. Problem solved, right?
Not quite. Remember all the heat that has already been absorbed by the oceans? It will be slowly released upward, into the air. (You’ll recall that heat rises.) So even if we “solve” our carbon problem at its source tomorrow, we haven’t changed the reality that the oceans will continue to release stored heat for a long time. When you put tipping points and lag times together, you can see why humans find it so hard to see the danger we are putting ourselves in. Inch after inch, crack after crack, our actions produced few obvious negative consequences and many positive, enjoyable ones. We got away with murder.
Until now. Now we face the cascading lag times and self-reinforcing cycles of consequence labeled “doom loops” by experts. Those experts are helping us understand more every day about where tipping points and lag times have brought us.
For example, we know that ice reflects solar energy back into space, keeping the Earth’s overall temperature relatively stable. When the ice melts away, ice-free land and water absorb even more heat, which further accelerates the rise in temperatures, pushing ice to melt faster and faster and faster. We know that we are either very near or slightly past the tipping point for the planet’s ice.
We also know that as ice melts and oceans warm, seawater expands and sea levels rise. A large percentage of the human population lives along coastlines that will be affected by rising seas. In addition, as ice melts, we know that huge quantities of methane held in permafrost on land and under shallow seas will be released, supercharging the overheating process, which speeds up all the other systems toward their tipping points.
We also know that one of the most powerful ocean currents that redistributes heat in (and beyond) the Atlantic has already been slowing and weakening because of melting ice flowing into the North Atlantic. We know that when ocean currents change, weather patterns change. Predictable weather patterns become unpredictable. Extreme and unseasonal droughts, floods, freezes, hurricanes, tornadoes, and heat waves kill crops, animals, and people.
Many experts believe it is already too late to stop these interrelated tipping points, based on the amount of carbon we have already pumped into the atmosphere and the lag time in accumulating effects. We don’t know for sure which tipping points have already been crossed, but we do know that if we burn all the fossil fuels that Exxon, Shell, Chevron, and other oil companies already own, we will turn our lag times and tipping points into doom loops, forcing us into scenarios nobody would ever willingly enter.