A major new paper concludes that climate models are invalid because they overlook interactions between the Earth and human systems such as overpopulation, demographics, migration, economic growth and inequality.
…the major scientific models of Earth-Human System interaction do not bidirectionally (interactively) couple Earth System Models with the primary Human System drivers of change such as demographics, inequality, economic growth, and migration.
The researchers argue that current models instead generally use independent, external projections of those drivers. "This lack of two-way coupling makes current models likely to miss critical feedbacks in the combined Earth-Human system,"…
"Without including the real feedbacks, predictions for coupled systems cannot work; the model will get away from reality very quickly."
Co-author Matthias Ruth, Director and Professor at the School of Public Policy and Urban Affairs, Northeastern University, said: "The result of not dynamically modeling these critical Human-Earth System feedbacks would be that the environmental challenges humanity faces may be significantly underestimated. Moreover, there's no explicit role given to policies and investments to actively shape the course in which the dynamics unfold. Rather, as the models are designed now, any intervention—almost by definition—comes from the outside and is perceived as a cost. Such modeling, and the mindset that goes with it, leaves no room for creativity in solving some of the most pressing challenges."
"The paper correctly highlights that other human stressors, not only the climate ones, are very important for long-term sustainability, including the need to reduce inequality'', said Carlos Nobre (not a co-author), one of the world's leading Earth System scientists,... [emphasis mine]
The Climate Change rate is 13% faster than we thought, and accelerating.
According to new research published today in Science Advances, the world’s oceans are warming up at an overall rate that is 13% faster than previously thought. Study authors used a new methodology to gain a more refined picture of overall ocean warming. … in addition to the oceans having gained more heat, the study also found that the rate of ocean warming is accelerating.
… consider the fact that about 90 percent of the total extra heat … ends up in the world’s oceans. For this reason, ocean heat gain is probably a better determiner of overall global warming than atmospheric heat gain.
… what this accelerating and higher than expected ocean heat gain means is that we have less time … to achieve a necessary reduction of emissions before various harmful and catastrophic effects from climate change get locked in. [emphasis mine]
(Total ocean heat gain in the top 2000 meters as found in Improved estimates
of ocean heat content from 1960 to 2015.)
The evidence increases and the consequences become clearer. We do not need more coal, oil or gas burned on this planet. We need research, development, and production of alternative energy sources.
Charismatic leadership will be required, given that we have a very dangerous leader at the helm of our nation now. We need a better-educated public who understands our peril and joins with others for a common purpose.
Knowledge, inspiration, vision, can motivate a public that cowers under the boot of a destroyer.
The study confirms past estimates of likely rapid climate change over the next century if there are not major climate-change policies. It suggests that it will be extremely difficult to achieve the 2°C target of international agreements even if ambitious policies are introduced in the near term. [emphasis mine]
I just heard about a new Hansen paper on how the freshwater lens effect from glacier melt in the Southern Ocean and the North Atlantic will slow thermohaline circulation, causing strong storms.
There are the strong storms which will come out of it. It also does not convey the heat out of the tropical oceans as well, nor the cool/cold out of the Arctic and Antarctic. In the shorter run, the higher amount of fresh water coming off of Greenland and Antarctica (less so) will preserve the polar ice - but just for a couple of years. In the mean time, the tropics will become warmer and much wetter.
The problem is that the fresh water from these glaciers is less dense than sea water. With the salinity being equal, the cold water is less dense than warm water, so it is on top. Ocaean currents stay in layers. So, the cold fresh water stays on top, keeping the warm saltier water underneath, so it's not giving off any of its heat. As it moves somewhat south, rather than the current giving off heat, it is absorbing heat. So, there's colder more extreme weather at high latitudes. As it goes farther south, it seems to get caught in some of these eddies, and effectively stop. The current will keep moving, but more slowly.
Meanwhile, zonal flow in the atmosphere is breaking down with higher global temperatures, and the whole thing leads to stronger storms.
The eddies in the current - there's one in the Atlantic off the coast of Morocco, and another one that formed just a couple of years ago off the coast of Oregon. Mathematical models seem to indicate that these will generate much stronger storms - as well as making Morocco-Nigeria much wetter (and inland), there being more snow in the Oregon/Washington/Northern California mountains - but more rain in the spring, so it would melt away earlier in the year, leading to both floods and droughts downstream.
In the summer, everything is likely to be hotter and drier.
A new study shows that the scariest climate models are the most accurate.
The researchers focused on comparing model projections and observations of the spatial and seasonal patterns of how energy flows from Earth to space.
Their strategy relied on the idea that the models that are going to be the most skillful in their projections of future warming should also be the most skillful in other contexts, such as simulating the recent past.
"Our study indicates that if emissions follow a commonly used business-as-usual scenario, there is a 93 percent chance that global warming will exceed 4 degrees Celsius (7.2 degrees Fahrenheit) by the end of this century. Previous studies had put this likelihood at 62 percent."
In less than 3 minutes, Steve Sherwood explains why climate sensitivity is about 3.7, meaning that uncertainty in climate models due to clouds is now resolved toward Earth warming faster.