CHANGED CLIMATE: California's San Francisco Bay area will face significant changes as global warming continues.
Image: Edward, courtesy Flickr
Climate change and expanding seas could cause the waters beneath the Golden Gate Bridge to rise 3 to 4 feet by century's end, a new study finds.
Warmer temperatures also would transform the environment of the San Francisco Bay and Sacramento-San Joaquin Delta, a system that provides water for 25 million people and irrigates $36 billion in annual crops. Changed conditions would affect native species, including the endangered delta smelt and winter-run chinook salmon, the U.S. Geological Survey reported in research published in the journal PLoS ONE.
"Virtually every aspect of the San Francisco Bay Delta system that we looked at is going to change substantially in the future," said James Cloern, a USGS scientist and the study's lead author. Less snowpack and faster-melting snow could lead to more frequent and intense flooding and droughts, he said.
"We have to really think about anticipated changes in the frequency of extreme events," Cloern said. "As global warming proceeds, we're going to experience combinations of environmental conditions unlike any we've seen in the past."
USGS looked at the likely effects of climate change using two models, one where the temperature rises 2 degrees Fahrenheit by 2099 and the other where it climbs 7 degrees by century's end. Researchers examined the impact on air and water temperatures as well as the frequency of extreme events.
The findings can help government agencies and conservation groups as they plan strategies to adapt to the changes, Cloern said. Those include the city of San Francisco and the state's San Francisco Bay Conservation and Development Commission, which is studying how to protect water supplies and sustain native species. San Francisco, Cloern said, believes rising seas will affect 270,000 people and threaten more than $60 billion in infrastructure, he said.
"The protection of California's Bay-Delta system will continue to be a top priority for maintaining the state's agricultural economy, water security to tens of millions of users, and essential habitat to a valuable ecosystem," said USGS Director Marcia McNutt. "This new USGS research complements ongoing initiatives to conserve the Bay-Delta by providing sound scientific understanding for managing this valuable system such that it continues to provide the services we need in the face of climate uncertainty."
Widening a partisan divide
The findings could also have political punch. There is a partisan divide over water policies and fish protections in the Bay Delta region.
Rep. Devin Nunes (R-Calif.) earlier this year offered H.R. 1837, which would repeal a 2009 law on central California water uses and replace it with 1994 rules from an agreement known as the Bay-Delta Accord. The measure would set compliance with the Endangered Species Act to that year. Nunes and other GOP lawmakers at a House Natural Resources Subcommittee on Water and Power hearing in June argued that the existing law prioritizes fish over people. The law, which stems from a court settlement on water flows, salmon and endangered species, places limits on the amounts of water certain farmers can take for irrigation.
"Protecting endangered species is a worthy goal, and worthy goals need to be pursued with common sense and sound science, not left-wing ideology and junk science," Subcommittee Chairman Tom McClintock (R-Calif.) said at that hearing.
USGS researchers found that climate change would alter conditions in the Bay Delta, affecting the fish that also are part of the current fight over protections. Both the moderate and the faster increases in temperature would lead to water that is warmer, saltier and less muddy.
That's the opposite of the conditions best for the endangered delta smelt.
"As temperatures warm, the habitat becomes less friendly for delta smelt and more friendly to introduced species like blue gills," Cloern said, adding, "what's a new perspective here is that one of the consequences of climate change is progressive favoring of the introduced species and disfavoring of the native species."
The habitat conditions changed under both the 2- and 7-degree temperature increase scenarios, he said.
"The habitat changes are bigger and faster in the [7-degree] warming scenario," Cloern said. "So it's just a question of how fast things will change. Even in the moderate warming scenario, there are predictions of big changes in the delta habitat as this century unfolds."
Uncertainty about rain, little uncertainty about sea level rise
Climate change could also affect precipitation in California, though the two models USGS used in its research produced different results.
If temperatures rise 7 degrees by century's end, the state's climate will become significantly drier, Cloern said. With the 2-degree temperature increase, California would not see a noticeable impact on precipitation patterns. That difference has been seen in other climate change research, he said.
There were longer droughts, however, in the model using a 2-degree temperature increase.
"Even in the moderate warming scenarios, there are going to be changes in California's water supply," Cloern said, but "there's real uncertainty about whether California will become drier or wetter."
"There's little uncertainty about sea level rise," he added. "Both of the scenarios we used project substantial levels of sea level rise, whereas the models did not agree on the direction of change of California's precipitation."
Looking at sea level rise, water would rise 37 inches in the moderate warming scenario and 48 inches in the faster model. The measurements reflect what would happen at the tide gates beneath the Golden Gate Bridge, which is the entrance to the Bay Delta. Water levels will rise less closer to the shore, Cloern said, though the research only looked at the one site.
"It's a powerful conclusion that these two different scenarios give rates of sea level rise that aren't that different from one another," Cloern said.
Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500
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26 Comments
Add CommentA question I have is whether we should try to protect species that can no longer be sustained by the changed environment. I think that the balance of species should adapt to the changed conditions without the interference of man. We have already mwessed with the environment without understanding the consequences and to continue doing so for purely altrusic reasons is meaningless.
Reply | Report Abuse | Link to thisTom McClintock - Ace graduate of the school that teaches republicans to accuse their detractors of what they themselves are guilty.
Reply | Report Abuse | Link to this"...worthy goals need to be pursued with common sense and sound science, not left-wing ideology and junk science," said by the wingnut ideologue who knows nothing BUT junk science.
Is this another one of the the IPCC edicts developed by WWF funded undergrads and grad students masquerading as grown-ups and world authorities?
Reply | Report Abuse | Link to thisJust checking... there's so much of that going on in the IPCC that one has to be specific.
I find it hilarious that now that Durban fast approaches the usual suspects are cranking up there propaganda machines and spewing forth massive ammounts of garbage, junk science and pseudo-science.
This means you the Gaul.
You do that and you'll be gone too.
Reply | Report Abuse | Link to thisWe can only support x amount of life. Fish die...people are next.
All life has to be in balance for us all to survive.
Okay, so what is REAL science to you, then? Really, what bit of Real Science(TM) would YOU add to this debate?
Reply | Report Abuse | Link to this“Climate change and expanding seas could cause the waters beneath the Golden Gate Bridge to rise 3 to 4 feet by century's end, a new study finds.”
Reply | Report Abuse | Link to thisFollowed by all the other predictions.
Sprinkeling predictions with , “If” & “Could”, etc. allows the allarmists to predict anything. It does not matter how flimsey the basis for such qualified predictions, one irrefutable fact is that huge research budgets flow from these scare tactics. According to the chief of the IPCC humans are responsible for earthquakes too.
‘If ifs & buts were candy & nuts, oh how happy we’d be.’
Well, this movement has indeed turned ifs & buts into candy & nuts with the gullible taxpayers footing the bill.
I wonder if there's any prospect of SciAm returning to a policy of reporting fact at any stage? If not, perhaps it's time to stop calling it Scientific and just publish "The American".
Reply | Report Abuse | Link to thisI have some real science... "real" meaning driven by something other than a socialist agenda to drive centralized control of economies. Google "Vostok Survey" images and note that the ~150k year warming cycles are preceded by several thousand years of heavy dust in the atmosphere. Thats exactly whats happened on the current cycle. There is little argument that the climate is warming, here is scientific proof that mankind has little if no effect on it. I really want to once again respect Scientific American as a source of science free of of political slant. Apparently thats not yet the case. Fire your Marxists and lets get back to science.
Reply | Report Abuse | Link to thisWell, that's right up there with if you sail too far you'll fall off the edge of the world! Fish die, humans eat something else, probably evolve to eat something currently not considered edible (the way that we adapted to drinking cow's milk, for example). Your equation is correct only in so far as x is quantifiable but if evolutionary theory teaches us anything it's that x is and possibly always will be much larger a number than the largest number we can imagine it to be. Species, maybe even our own, come and go but life has a habit of hanging on in there against all the odds.
Reply | Report Abuse | Link to thisThe essential question is "Who will determine how much life is in "x"?" if we use your zero sum theory. Would this be determined by a bureaucrat driven by political ambition? Perhaps bureaucrats should be disguised as scientists as they are today to add, as C.S Lewis describes it,with a small amount of truth to make the lie far more powerful and believable.
Reply | Report Abuse | Link to thisAnother hodgepodge of speculation...not worthy of the 'Scientific' of Scientific American.
Reply | Report Abuse | Link to this"If, might, could, may..."
If I climb a tree I might fall out and could break my neck and may diet.
GW cultists are getting more and more silly.
Did you read the article? Its liberal-progressive tripe.
Reply | Report Abuse | Link to thisActually, I was referring to certain species being replaced by other species more suitable to the changed enviroment. And, yes, that should also apply to man. If we cannot adapt, our replacement will show up and may even be much more ECO friendly than we have been.
Reply | Report Abuse | Link to thisReal science is by definition measurable, testable and falsifiable. If you use those three yardticks in reviewing the above article it falls somewhere in the continuum between sci-porn and eco-jihadist propaganda.
Reply | Report Abuse | Link to thisBoth of which seem to be the end points for discussion beyond which the Climate Editors are too cowardly to venture.
Sorry, but SCIAM ceased being a serious science magazine long ago. It serves as a warning to America as to what happens when you let political agenda color your views of the world around you.
As Robert DeNiro said in the movie "The Deer Hunter" in the famous scene where he holds up a bullet and lectures his scatter brained hunting buddy: "This is this, it isn't something else... this is this."
The Alarmist movement needs to get that through their brains as well. No stinking fetid mountain of heaped up pseudo-science trumps a single testable theory, or repeatable, measurable and falsifiable experiment.
So far the alarmist offer nothing but fear.
It is encouraging that people are waking up to the scare campaigns. There is another one being launched in the run-up to the Durban conference. We can expect daily announcements. “Another crack in Antarctica’s Pine Island Glacier.” Are large icebergs unusual in Antarctica?
Reply | Report Abuse | Link to thisClimate skeptic Richard Muller has just announced that he has changed his mind after performing an extensive study of the global warming data. He now agrees that it is real, as he explains in the Wall Street Journal. See:
Reply | Report Abuse | Link to thishttp://online.wsj.com/article/SB10001424052970204422404576594872796327348.html
And the data is at:
http://www.berkeleyearth.org/Resources/Berkeley_Earth_Summary_20_Oct
curmudgeon says: "Species, maybe even our own, come and go but life has a habit of hanging on in there against all the odds."
Reply | Report Abuse | Link to thisI think the people who are trying to oppose Global Warming are specifically trying to prevent the extinction of humans. Sure, we may want species to survive, but we have a particular attachment to this one. If we kill off all the fish, maybe we'll eat jellyfish. If we kill off all the jellyfish, maybe we'll eat plankton. If we kill off all the plankton, maybe we'll eat Soylent Green. If we kill off all the Soylent Green . . . hey, wait a minute!
I don't think we should take the extinction of any species lightly. They are all part of our life support system. If you start saying, "Oh, that's one's not important, go ahead and kill it off," then where does it stop? When there is nobody left but corporations? Corporations and their spokespeople seem to think that they will be okay even if the environment is poisonous to humans. Do corporations count as "persons" when it comes evolution? If all the humans are dead, will they find a way to reproduce?
Wow! Was the comment by JamesDavis bad enough that it had to be deleted? I didn't get to read it and I know he is a bit over the edge, but he does sometimes make me laugh. (at him of course)
Reply | Report Abuse | Link to thisThis is yet another of numerous Scientific American articles that are not reporting science, but are merely publishing wild propaganda for those that fear the emission of CO2. The premise of the article has minimal valid scientific merit. Let’s review some of what was written in the article and the fears:
Reply | Report Abuse | Link to this1. Climate change and expanding seas could cause the waters beneath the Golden Gate Bridge to rise 3 to 4 feet by century's end
My analysis- Sea level has been rising at less than 1 foot per century and there is not any data or a reliable model to demonstrate there is any reason to forecast a significant change to what has been occurring for the last 20 years.
2. Warmer temperatures also would transform the environment of the San Francisco Bay and Sacramento-San Joaquin Delta , a system that provides water for 25 million people and irrigates $36 billion in annual crops. Changed conditions would affect native species, including the endangered delta smelt and winter-run chinook salmon
My analysis- Notice here that the article is written in a way to promote fear, without really stating anything to fear or to dispute. It doesn’t actually state that any change to the climate would be harmful in any way. It simple references the value of the crops and the number of people there. In fact, there is absolutely no reliable evidence of any potential harm coming to the area by a potential temperature rise. I challenge any of those fearing the future to demonstrate the basis of you fear. Is it a GCM that has not accurately predicted actual observed conditions, but still gets referenced in reports?
3. Less snowpack and faster-melting snow could lead to more frequent and intense flooding and droughts
My analysis- see comment #2 it is the same here.
4. "We have to really think about anticipated changes in the frequency of extreme events," Cloern said. "As global warming proceeds, we're going to experience combinations of environmental conditions unlike any we've seen in the past."
My analysis- see comment #2 it is the same here.
5. Cloern said, believes rising seas will affect 270,000 people and threaten more than $60 billion in infrastructure,
My analysis- see comment #1
I am not a republican, but how can anyone find fault with the statement:
"Protecting endangered species is a worthy goal, and worthy goals need to be pursued with common sense and sound science, not left-wing ideology and junk science," Subcommittee Chairman Tom McClintock (R-Calif.)
"...socialist agenda to drive centralized control of economies.... Fire your Marxists and lets get back to science."
Reply | Report Abuse | Link to thisAh, the Cold War bogey men again! How's it goin', comrades? Still working on that plan for the precious bodily fluids?
It appears to me that you are cherry picking MrDrT's comment, then extrapolating out to your own fantasies, a favorite technique of the liberals. Put your own words in his/her mouth and then condemn him/her because of them.
Reply | Report Abuse | Link to thisBy the way, if you truly believe that the socialists have given up their Marxist agenda, you reveal your own failure to grasp reality.
Sisko said: "My analysis- Sea level has been rising at less than 1 foot per century and there is not any data or a reliable model to demonstrate there is any reason to forecast a significant change to what has been occurring for the last 20 years."
Reply | Report Abuse | Link to thisThe IPCC report shows sea level rise accelerating. Would you mind providing the details of your "analysis"? Do you have any data to show that the calculated amount of meltwater from Greenland is not accurate? Data shows that the amount of ice lost from Greenland rose from 137 to 286 Gigatonnes between 2003 and 2009. No need for a model to understand that. The low-noise gravimetric satellite data agree with ground based estimates on this number.
Does your so called "analysis" provide an probability of the melting of the rest of the Greenland Ice Sheet? You're right that the models are not accurate. They have been too conservative by far. The Greenland glaciers are melting faster than any model predicted. If the Greenland Ice Sheet melts, it will raise the sea level by about 7.2 meters, over 20 feet. How probable is that in your "analysis"? If the Antarctic Western Ice Shelf collapses, it will raise it by 5–6 meters. What is the probability of that in your "analysis"? And you have to show your math to get any credit.
Sisko says:
Reply | Report Abuse | Link to this'I am not a republican, but how can anyone find fault with the statement:
"Protecting endangered species is a worthy goal, and worthy goals need to be pursued with common sense and sound science, not left-wing ideology and junk science," Subcommittee Chairman Tom McClintock (R-Calif.)'
Translation: "The oil and coal industries own both political parties and won't let me tell you the truth that the science is already well established and AGW is quite proven. It is right wing ideology and pure mindless, psychopathic greed that prevents us from doing anything about the problem and want to pretend to keep studying it to death. OUR death."
MrDrT says: "Google "Vostok Survey" images and note that the ~150k year warming cycles are preceded by several thousand years of heavy dust in the atmosphere. Thats exactly whats happened on the current cycle."
Reply | Report Abuse | Link to thisI Googled Vostok Survey and found data that shows the 150K cycle should have peaked recently and the temperature should now be cooling. Instead it is zooming upward.
Greenmind
Reply | Report Abuse | Link to thisI track sea level rise from the most accurate data in existence which is TOPEX satellite records.
Here they put the data into a pretty chart
http://sealevel.colorado.edu/current/sl_ib_global.txt
http://wattsupwiththat.com/2011/10/15/message-to-maldives-president-your-claims-are-bs/
Sisko
Reply | Report Abuse | Link to thisThe data in that first link only covers sea levels since 1992, not enough time to evaluate acceleration. And even so it is only historical data, when you claim to be predicting future sea level rise. Again, what are your probabilities for the melting of the Greenland Ice Sheet or the Western Antarctic Ice Shelf?
The article by James Cloern (the one that this SA item reports on) evaluates what would happen if a new technique in estimating sea level rise turns out to be true. The Cloern article references a different article by Stefan Rahmstorf that uses a "semi-empirical" approach to see if it is more accurate than the IPCC approach. The real controversy is in that article, not the Cloern one. Here is a link to that article.
http://www.nature.com/climate/2010/1004/full/climate.2010.29.html
The IPCC assumed that continental melting would NOT accelerate as global warming increased, and the semi-empirical approach assumes that it does. It claims more accurate modeling of past melting of glaciers, and predicts much higher sea level rises by the end of the century. Essentially, it says that ice cubes melt faster in warmer air temperatures, where the IPCC said they melt at the same rate. Do you have reason to dispute either of them?
With the swings in weather that is associated with warming, you might get very warm days that cause far more melting than a higher but more even temperature.
I remember a couple of years ago when the Sierra had a series of heavy snowstorms that increased the snowpack to record levels. Then some unusual spring storms brought unseasonable warm rain to the mountains and melted a lot of the snowpack.