Study on how soon we will hit 1.5°C temperature increase
Quote:Abstract
Global temperatures could exceed 1.5 degrees Celsius above their preindustrial levels within the next 15 years, according to a new scientific study, crossing the first threshold under the Paris climate agreement and placing the world at a potentially dangerous level of climate change.
Remember the three main icesheets are on the verge of collapse, well almost so. More warming would not be good. Remember, the Eemian period 125,000 years ago was maybe a bit hotter than today—and had sea levels nine metres higher than today.
Quote:The study focuses on a natural planetary system known as the Interdecadal Pacific Oscillation, or IPO (it’s also sometimes referred to as the Pacific Decadal Oscillation). It’s an alternating pattern of ocean temperatures that shifts periodically between warm and cool phases, helping to drive temperature and weather patterns all over the world.
During cool, or “negative,” phases, tropical regions of the Pacific Ocean tend to be colder, and the global mean temperature is lower. The system is similar to the El Niño/La Niña cycle, the major difference being that phases of the IPO tend to last much longer — sometimes a decade or more. The phenomenon is believed to be a natural form of climate variability unrelated to human-caused climate change, although it does have the potential to influence the progression of global warming.
http://onlinelibrary.wiley.com/doi/10.1002/2017GL073480/fullSo, what phase is the IPO/PDO in and is it likely to move to another phase?
Quote:For most of the 2000s, the IPO has been in a negative phase, and scientists think its cooling effect has helped to slightly offset the effect of climate change. . .
Quote:Many scientists believe that the planet is now transitioning back into a positive, or warm, phase, which could amplify, rather than offset, human-caused climate warming. This means we could reach milestone temperature thresholds faster than we would if the IPO had remained in its negative phase.
That’s the conclusion of the new study, written by Henley and Andrew King of the University of Melbourne. Using model projections of future climate warming under a business-as-usual scenario, they suggest that the Earth could hit the 1.5-degree temperature threshold as early as 2025, while the continuation of the negative phase probably would delay this event until after 2030.
https://www.washingtonpost.com/news/energy-environment/wp/2017/05/09/earth-could...With those three huge icesheets already on the verge of collapse hitting 1.5°C increase is not what we want to do.
So, bugger off any new coal fired generators, time to implement an emissions intensity scheme or a fullblown, traded cap and trade ETS.
How can we protect against sea level rises? Better start implementing that.
Phase out coal ASAP and replace with renewables plus nuclear as a backup. Plenty of aging coal fired generators that will be shut down soon anyway.
What coastline will go regardless of what we build as sea defences? What will that do to acquifers? LOTS of policy issues.
The topic of this thread.
Will the extra warming to 1.5°C see thresholds being passed? Irrevocable melting of icesheets say?