How bad is bad? A sobering Recap of recent AGW findings
I am using a fantastic post by Intenzity as a jumping off point.
He wrote an excellent post about this review page here:
I have written many times that the biggest issue with climate models has not been that they produce results which are too grim, but rather that the actual observed data and actual observed effects of AGW are almost always worse than predicted.
This is due to a number of reasons. While we have the largest drivers of climate change well modeled and pretty well understood at this point, there are still numerous feedbacks that interact in ways that we do not clearly understand. They end up amplifying each other more than expected.
Further, our actual emissions are outstripping projected emissions. China has surpassed the US in emissions and U.S. emissions have not been reduced. Many models assume some degree of responsibility from someone. Many models do not adequately take into account just how much methane is starting to come up from the oceans and the various thawing bogs. However they underestimate the growth in output of emissions, we keep pushing the global climate system harder than expected.
We also really don’t know how to model sudden break ups in ice sheets. The sheets are going much faster than expected and as reported earlier, will cause catastrophic flooding of coastal regions.
So first off, here is a very fresh review of yet another way we know we are causing AGW.
From the Abstract:
With increasing greenhouse gas concentrations, the surface and troposphere are consistently projected to warm, with an enhancement of that warming in the tropical upper troposphere. Hence, attempts to detect this distinct ‘fingerprint’ have been a focus for observational studies…Paralleling developments in observational datasets, increased computer power and improved understanding of climate forcing mechanisms have led to refined estimates of temperature trends from a wide range of climate models and a better understanding of internal variability. It is concluded that there is no reasonable evidence of a fundamental disagreement between tropospheric temperature trends from models and observations when uncertainties in both are treated comprehensively
But let’s look at the consequences:
The consequences to sea level are that we are looking at a two meter rise in ocean levels being likely by the year 2100. That means New York, Miami, New Orleans, Houston, large parts of LA, London, Tokyo and more simply gone.
It means close to 200 million people without homes or businesses.
From this letter to Nature, we see that the ice sheets are going much, much faster than expected.
To see what some of this dynamic thinning looks like from the British Antarctic Survey look here:
Image: pritchard_etal_antarc_plus_.jpg
Here is the press release:
In fact, Antarctica is going four times faster than expected.
Here is my page on this. I referenced an older paper. Since then, as the problem was better studied and more data has come in. It is much worse.
But of course, it gets much, much worse.
Droughts will threaten much of the rest of the world.
Look at this from NOAA:
And look at this PNAS:
The severity of damaging human-induced climate change depends
not only on the magnitude of the change but also on the potential
for irreversibility. This paper shows that the climate change that
takes place due to increases in carbon dioxide concentration is
largely irreversible for 1,000 years after emissions stop
And what are we signing up for the next thousand years exactly?
Places like the American South West, large portions of Africa, Central Asia, the Middle East, Latin America and most of Australia will become uninhabitable.
This will mean hundreds of millions to billions without food and water. Get real with it.
But I have saved the worst for last.
Do you like breathing? If you do, you will find that killing the oceans is a very bad idea. Aside from serious ocean acidification, ocean phytoplankton are down by over 40% in the last several decades. Dead zones in the ocean are spreading and becoming permanent.
Let that sink in. This is the base of the oceanic food chain and the source of most of our oxygen.
Look at this from Nature.
Abstract:
In the oceans, ubiquitous microscopic phototrophs (phytoplankton) account for approximately half the production of organic matter on Earth. Analyses of satellite-derived phytoplankton concentration (available since 1979) have suggested decadal-scale fluctuations linked to climate forcing, but the length of this record is insufficient to resolve longer-term trends. Here we combine available ocean transparency measurements and in situ chlorophyll observations to estimate the time dependence of phytoplankton biomass at local, regional and global scales since 1899. We observe declines in eight out of ten ocean regions, and estimate a global rate of decline of ~1% of the global median per year. Our analyses further reveal interannual to decadal phytoplankton fluctuations superimposed on long-term trends. These fluctuations are strongly correlated with basin-scale climate indices, whereas long-term declining trends are related to increasing sea surface temperatures. We conclude that global phytoplankton concentration has declined over the past century; this decline will need to be considered in future studies of marine ecosystems, geochemical cycling, ocean circulation and fisheries.
repost from:
and more on the topic here:
Now get this straight. We need oxygen to live. So does every other animal on the planet that we like. We are destroying that.
We are looking at a cascade of effects. Between drought, crop failures, and destroyed aquatic life, we are looking at billions of people around the globe without adequate food or water. We are looking at most of the major American cities destroyed and flooded out. All of that by 2100.
We are looking at a global catastrophe that will kill billions - and if the seas cross an oxygen tipping point, all of us.
When I say that billions will die this is not an hyperbole. The cold scientific facts are that our civilization is on a precipice. We can act to prevent our collapse or we can plunge into ruin.
I have not even discussed the spread of contagion in detail here. My other post, Climate change: A matter of life and death, goes into that somewhat.
I pointed out there that we are seeing cases of dengue fever in Italy, France and Spain.
Since that post, we have seen it in Miami.
