Are we heading to Hothouse Earth?

This past week the news have not been any getting better. The heat waves are still affecting countries: in South Korea, temperatures around +39 are said to prevail at least 23 consecutive days and in southern Europe, temperatures are still abnormally high.

In California, wild fires are ranging to the extent that now the military has been called to help out. Reinforcements have also arrived from Australia and New Zealand, while the Yosemite National Park is closed “indefinitely” due to the fires.

One of the very first fire tornadoes has made its appearance in California although authorities are still debating what to officially call it.

This is keeping with last week’s theme of “unprecedented” when so many new records are being broken.

As a scientist, and someone who is researching climate change for living, many of these events are more than alarming.

But what do we really know about how the Earth has changed?

Hothouse or Stablished Earth?

Conveniently just this week a perspective by Steffen et al. (2018) was published on what our Earth System is actually doing at the moment and where we are likely to be heading.

The Paris Agreement was put in place in 2015 with the aim of keeping global temperatures below 1.5 degrees of warming, or at least 2 degrees.

Yet, globally emissions are still going up and the 2 degree warmer world is starting to look more likely.

However, the authors of this new paper argue that going beyond 2 degrees is actually a potential emergency for our planet where many of the feedback processes that currently cool the Earth might actually start warming it.

Once particular tipping points have been passed, it is not easy or even possible to try to make major changes to redirect the direction of global change.

Range of different tipping elements are also observed where different increases in temperatures are likely to impact on a range of processes, which interact and accelerate warming:

STeffen et al_TippingELements.jpg

Our understanding of these processes, their interactions, and their consequences is still very limited and Steffen et al. 2018 suggest a range of further research priorities that scientists could pursue to unveil some of this information.

There is also the notion that once we go past 2 degrees, and tipping points are activated, it could be likely that we are not able to control or manage different processes as noted by one of the authors Johan Rockstrom: 

“We are the ones in control right now, but once we go past 2 degrees, we see that the Earth system tips over from being a friend to a foe. We totally hand over our fate to an Earth system that starts rolling out of equilibrium.”

It is not a pretty picture.

But what the authors do note is that we are not necessarily there yet and that we still have a choice: we can attempt to keep warming under 2 degrees and perhaps push the Earth System deliberately towards “Stabilised Earth” scenario.

But even if we could live in a Stablished Earth, it will be still very much warmer than anything that the Earth has experienced, meaning adaptation will remain a constant feature in such challenging circumstances.

Is there hope for adaptation?

The question that I keep asking is when do we know that we have gone too far in the pathway given the complexity of tracking global processes, and their interactions.

And more importantly, what can we do even to adapt to a constantly changing context where feedbacks, tipping points and processes could accelerate changes at scales never seen before?

In a Hothouse Earth, we are however not likely to be able to adapt: as the authors note, “a Hothouse Earth trajectory will likely exceed the limits of adaptation” (Steffen et al., 2018, p. 5).

Yet, the hopeful message is that we still have a choice and this is very much why we need stronger action and global commitment to act on climate change.

While the California fires and European heatwaves cannot be necessarily directly linked to climate change yet, there is the potential that this is what we need to start adapting to.

This then calls for changes in how we manage emergency and disaster services, what kind of fire fighting equipment is available and used, and how we train the staff and volunteers to cope with these new fire conditions.

These are things we can already do while maintaining flexibility for other options in how we manage climate related risks.

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