Picture a bunch of small dominoes that do not have the ability to push over a bigger domino by themselves but when enough of the small dominoes push against the bigger domino, it too can fall. That is a tipping point. When the next big domino falls, it then initiates a new state that can then build in force towards the next tipping point.
An in depth discussion of tipping points can be found at RealClimate. The purpose of this article is to give you some context to understand what tipping points in our climate system mean, and the relevance of that understanding in the context of human impacts.
As tipping points are reached and surpassed, the ability to change, or reverse the effects become increasingly challenging and expensive. It is of course important to understand that there may very well be, or likely is a point at which the effects become irreversible which could or would most likely result in the end of civilization as we know it, or worse.
This effect occurs when the overall climate system becomes able to amplify itself in one or more areas of the climate system. Examples include:
- Snow Albedo
- As the reflectivity of ice disappears due to warming the climate responds by warming more because the ice no longer reflects the solar energy that it used to. This results in melting the ice faster.
- Water Vapor Feedback
- As the climate system warms, the ocean absorbs more heat, as the ocean absorbs more heat more water evaporates. Since water is also a greenhouse gas, the greenhouse effect is able to trap more heat which in turn allows the oceans to warm further, which causes more evaporation, which warms the climate system further, and so on…
- The North Pole
- The Arctic Ice in the summer melt season is rapidly disappearing. Once the ice in the summer is gone, the darker water will absorb the sunlight whereas if the ice had been there, the sunlight would have been reflected back into space.
- The Northern Amplification Effect
- The northern hemisphere is mostly land which is easier to heat than the southern hemisphere, which is mostly water. Land heats faster than water so as the planet warms up, the northern hemisphere heats faster. The warming will cause more warming of the oceans which will increase the heat content as the ocean cycles overturn. his feeds the Water Vapor Feedback described above.
These are only a few of the expected tipping points and affects along the path of a warming world. Here are some additional tipping points occurring as the planet warms:
- Regional increases of floods/intensity (current)
- Indian Summer Monsoon shift (current)
- Regional increases of droughts/intensity (current)
- Shifting of the East Asian monsoon seasons (current)
- Increasing Hurricane and Typhoon intensity (current)
- Increases in snowfall due to moisture increase (current and increasing)
- Regional increases in susceptibility to fire (current and increasing)
- Africa Rainfall (10 years)
- The Amazon Rainforest converting to Savannah (20-30 years)
- The Boreal Forest (dieback within 50 years)
- El Niño Southern Oscillation (approximately 100 years)
- The Slowdown of the Atlantic Thermohaline Circulation (over next 100 years)
- The Greenland Ice Sheet contributing to sea level rise (increasing over 300 years)
- Destabilization of the West Antarctic Ice Sheet – WAIS (increasing over next 300 years)
Keeping in mind that modern human infrastructure developed in a climate state in and around thermal equilibrium the total current climate forcing is estimated to be higher that at any time in the last 7 million years. Modern humans have only been around about 20 -30,000 years.
The impacts of crossing these tipping points range from climate zone shift which will alter the food production capacity of the planet to the complete breakdown of the geopolitical infrastructure. If we allow the climate system to pass even a few tipping points the future of civilization, as we know it, will be at risk. If too many tipping points are passed the survivability of civilization will become the risk factor.
As it stands, with the current forcing and levels of atmospheric CO2, human civilization will go through many changes as economic stressers increase as climate zones shift.
Things to Consider
All in all, these effects are cumulative and amplifying with the warming effect. It is hard to define precisely where a particular tipping point is. It is better to understand that these effects are all increasing and amplifying the effect. This is happening as you read this. This will continue until mitigation becomes significant enough to reverse the amplification.
It is also important to understand that cost and difficulty increases the further the climate system moves into these various amplifications. The implications are severe damage to the global economy based on shifting infrastructure requirements to maintain quality or standards of living.
Note that there is also an economic tipping point to consider. Should we venture beyond the capacity to mitigate the amplification effects, civilization as we know is expected to breakdown. At that point it is reasonable to expect that the geopolitical structure will fail due to the inability to sustain functioning government.
Tipping points and feedback mechanisms in the climate system, in relation to the infrastructure that supports humankind’s current standards of living is a relationship that must not be ignored. Changes in the climate system will impact our infrastructure. That includes the monetary economy, resource capacity on land and in the oceans, species extinction, and virtually every aspect of our existence will be impacted.
Without immediate meaningful action, our governments will be stressed and most if not all will likely fail within this century. All indications are that working together increases survivability. But we must avoid passing deeply towards, or beyond the tipping points in order to mitigate the impacts.