Mind you, she is kind of cute:
Posted on 10/20/2009 5:11:26 AM PDT by crazyhorse691
Does human activity affect Earth's climate?
A simple question, no? It's been settled with a ringing "yes" among the scientific community. Yet, the so-called "climate debate" still pops up on editorial pages, political blogs and television talk shows. Apparently, we scientists have failed to explain to the entire public how we have come to understand the climate system. For this we owe another attempt to engage readers who still feel there is some doubt about the role of human activity in Earth's climate.
What follows is a no-frills, nonpartisan explanation of how a group of scientists working on a particular problem establish knowledge, what we know, and what we need to learn.
Understanding the underlying science is important, and not just because our elected leaders in Congress are debating policy options to combat global warming, including a cap-and-trade program aimed at reducing greenhouse gas emissions. It's also important that we move the discussion to what we should be arguing about -- how to mitigate the effects of global warming -- once we get beyond the distraction of false debates over whether climate change is real and caused by humans.
A good place to begin: On Saturday, the International Day of Climate Action will feature rallies and activities around the globe in an attempt to build momentum toward the U.N. Climate Negotiations in Copenhagen in December. See www.350oregon.org for a list of activities around Oregon.
And, Nov. 18, Al Gore, winner of the 2007 Nobel Peace Prize along with the U.N.'s Intergovernmental Panel on Climate Change, will speak at Keller Auditorium as part of the Portland Arts and Lectures Series.
How do scientists establish consensus, and what is the role of consensus documents like the IPCC reports?
The complexity of the climate system dictates that the details of its function are investigated by a large, interdisciplinary community of scientists, spanning fields from geology, hydrology and plant biology, to atmospheric dynamics and chemistry. The big picture comes into focus only when combining the results of specialists in each discipline, synthesizing an enormous body of scientific literature. The scale of this endeavor makes the establishment of consensus critical to the progress of science. We select an interdisciplinary team to periodically dedicate themselves to the review of the state of climate science.
Supported by the United Nations, the Intergovernmental Panel on Climate Change Working Group I conducts a thorough review of the peer-reviewed scientific literature on climate change science. This group is made up of experts in the various subfields of climate science, whose careers are built on their reputations as careful scientists. Their authorship amounts to further staking their reputation on the conclusions, encouraging the thoroughness and appropriate scientific skepticism of the review. These consensus documents provide an internationally recognized assessment of what we know, but also, very importantly, help guide the science forward by clearly stating where the greatest uncertainties remain.
What is the role of computer models? Why should we trust them?
Once the progression of research, scientific publication and peer review has arrived at an explanation of individual atmospheric processes, such as cloud formation, we need a testable framework for understanding the massively interconnected climate system. For this, we develop computational climate models. Multiple research groups around the world have independently developed such models, providing an excellent means of testing their accuracy: If 12 independently written computer models roughly agree on a prediction, it is highly unlikely to be due to a random error. Models are tested by running "hindcasts" (as opposed to forecasts) to determine their skill at predicting known past trends, from the well-measured 20th century climate to the ice ages. The evidence we have that human-induced emissions have contributed to the observed temperature increase over the 20th century is shown in the graphs below.
A set of climate models from research groups around the world was run with and without human-induced carbon dioxide emissions. The model results have some spread, corresponding to remaining uncertainties in the details of the climate system. However, the observed temperature trend only falls within the model range when the human contribution is included. Scientific progress occurs when observations (temperature increase) can be explained by a physical model (human-enhanced greenhouse effect). This is the same way that we understand gravity: I can't accurately predict how rapidly an object will accelerate towards the Earth without a model that incorporates the mass of the Earth.
What aspects of climate science are firmly established?
The global average surface temperature has increased by about 1.8 degrees Fahrenheit since 1850, with most of the increase since 1950. This warming can only be explained when including human contributions to atmospheric carbon dioxide (CO2 ). Before the Industrial Revolution, CO2 concentrations were less than 280 parts per million (ppm) for at least 1 million years; current atmospheric concentration is 385 ppm. Volcanic eruptions cause temporary cooling because of the particle haze they emit into the upper atmosphere; similarly, pollution emissions of particles from human activity have offset some CO2 warming over the past century, although the extent of this offset remains highly uncertain.
Warming is evident in other indicators as well, including rising sea level and decreasing polar sea ice and glaciers. Because CO2 remains in the atmosphere for centuries, and because oceans can store enormous amounts of heat, warming would continue for centuries even if emissions were to instantly cease.
What are some remaining uncertainties?
Here's what we should be arguing about: What level of CO2 in the atmosphere is safe? The specter of accelerating climate change and the possibility of crossing a tipping point are causing heightened concern among scientists. Doubling of pre-industrial CO2 levels (550 ppm) is one oft-cited target, for which average global temperatures are predicted to increase by 5.4 degrees Fahrenheit. In contrast, some climate scientists promote aiming to preserve conditions similar to those under which life on Earth developed, which would require reducing CO2 levels from the current level of 385 ppm to 350 ppm. These alternatives would require massively different carbon policy choices, and we must decide as a public how much risk we are prepared to take.
Is "geo-engineering" an option? A few governments around the world have recently begun discussing the possibility of offsetting global warming by introducing additional reflective particles into the atmosphere, to reduce sunlight reaching the surface. At what point do we become sufficiently concerned about crossing tipping points that we should seriously consider this as a stopgap measure? Almost no research has been conducted on geo-engineering, and many disconcerting open questions remain: Will the UV-protecting ozone layer be damaged, as it is after volcanic eruptions inject natural particles into the upper atmosphere? How far will the particles disperse, and how long will they remain aloft? How will plant life respond to diminished and more diffuse sunlight? If we wish to seriously consider such action as a "bridging" strategy while we work to reduce atmospheric CO2 to a safe level, urgent research is required to understand the consequences.
The ultimate question is, how do we get there from here? Once we define target CO2 , we must begin the difficult discussions of how to get there in a way that is globally equitable and cost-effective. This is the grand challenge, and one scientists are not equipped to address. We simply advocate for moving the "debate" from false distractions to the realm of finding solutions. We're all on this little spaceship called Earth together.
Juliane Fry has a Ph.D. in atmospheric chemistry from California Institute of Technology. She teaches chemistry at Reed College.
They can’t even get tomorrow’s weather correct and they expect me to believe they know what’s going to happen to the climate 20 years from now? Give me a break.
The acceleration of an object due to earth's gravity was predicted by Newton long before scientists even contemplated calculating the earth's mass. And in fact the calculation of an object in earth's gravitational field is independent of the earth's mass. And it was the observation of the motion that lead to the calculation of the earth's mass, not the other way around.
Excellent debunking of the global warming “consensus” can be found in Chill: A Reassessment of Global Warming Theory, Does Climate Change Mean the World Is Cooling, and If So What Should We Do About It? by Peter Taylor.
From amazon:
“Although the world’s climate has undergone many cyclical changes, the phrase ‘climate change’ has taken on a sinister meaning, implying catastrophe for humanity, ecology and the environment. We are told that we are responsible for this threat, and that we should act immediately to prevent it. But the apparent scientific consensus over the causes and effects of climate change is not what it appears. “Chill” is a critical survey of the subject by a committed environmentalist and scientist. Based on extensive research, it reveals a disturbing collusion of interests responsible for creating a distorted understanding of changes in global climate. Scientific institutions, basing their work on critically flawed computer simulations and models, have gained influence and funding. In return they have allowed themselves to be directed by the needs of politicians and lobbyists for simple answers, slogans and targets. The resulting policy - a 60 percent reduction of greenhouse-gas emissions by 2050 - would have a huge, almost unimaginable, impact upon landscape, community and biodiversity. On the basis of his studies of satellite data, cloud cover, ocean and solar cycles, Peter Taylor concludes that the main driver of recent global warming has been an unprecedented combination of natural events. His investigations indicate that the current threat facing humanity is a period of cooling, as the cycle turns, comparable in severity to the Little Ice Age of 1400-1700 AD. The risks of such cooling are potentially greater than global warming and on a more immediate time scale, with the possibility of failing harvests leaving hundreds of millions vulnerable to famine. Drawing on his experience of energy policy and sustainability, Taylor suggests practical steps that should be taken now. He urges a shift away from mistaken policies that attempt to avert inevitable natural changes, to an adaptation to a climate that may turn significantly cooler.”
Bottom line: Changes in cloud cover explain the warming to 1998 and the cooling since that time.
Fail.
How can she make such a bald and ridiculus statement. The average surface temp. is constantly changing both before and after the Ind. Rev.
The question isn't whether the models match historic data but rather can the models PREDICT future data. To date the answer on that is a flat out NO.
This is only about power. Power taken away from us and given to pin heads like the author who will grow fat while producing nothing.
This is the same method that is used for all other points of propaganda: attempting to make those who disagree feel alone, out of step, uninformed. There’s an enormous level of agreement, apparently, not just about global warming, but also about health care, and how phenomenal our President is, and ‘undocumented workers’, and etc. Along with the implied ‘concensus’ is the corollary: ‘and you are stupid and/or extremist and/or a whackjob if you don’t agree.’
Yes, That’s correct. And before the last Ice Age the co2 levels were higher than now. There was still an Ice Age. We are due for another one, and it will happen again, they are like clockwork.
I think the calculations of co2 impact are exagerated anyway. Methane is the one to fear.
A cold winter forecast for the North & East this year.
- And still no sunspots
Mind you, she is kind of cute:
Consensus gave us the flat Earth "science," Earth as the center of the Universe "science"...
Consensus isn't science. It is just the opinion of holier-than-thou pointy headed libtard acamedians looking for grant money.
Why not a Big Ice Age?
I see zero discussion of this issue. The present interglacial period is already considerably past the average length for interglacials.
Is there any particular reason to think we aren't going into a Real Ice Age?
Except the fact that the consequences will be so catastrophic nobody wants to think about it.
Unfortunately, OregonLive has a devoted following of PDX libtard mouthbreathers eager to jump on anyone who does not worship the progressive orthodoxy.
As evidenced by near-sighted groundhogs.
Forget it...she probably won’t date anything to the right of Karl Marx(Reed College is a very radical place).
The dear lady might want to consider that perhaps the climate models agree because all of their creators are attempting to demonstrate the same outcome. In other words, they are biased, a very common attribute of science that must be guarded against.
She can see no other explanation for global warming since 1850 but the hand of man. Man may indeed play some role, but I can’t help thinking that perhaps the emergence of the planet from the so called “Little Ice Age” and a return the warmer norms of earlier eras might have something to do with it.
She’s a kool aid drinker and I’m sure that makes her very popular on campus and at conferences.
Those replies are frightening.
There’s some good ones in there but most are “Bravo, tell those deniers a thing or two about a thing or two”
Scientists look for truth. Politicians establish consensus. As long as these "scientists" keep acting like politicians and don't look for the truth, I'll lend no credence to what they're trying to sell.
These "scientists" are nothing more than whores, bought and paid for by the communist green lobby through government grants. They are quite willing to tell their johns, from "Nobel laureate" algore on down, what they want to hear, and thus participate in the dismantling of the economies and living standards of the entire developed world for the sake of a hoax, just for a little cash. They are all beneath contempt.
Well, Dr Fry...there is a new theory out...maybe the sun has something to do with warming cooling of the planet. Hmmm, revolutionary idea...has to be radical.
I need someone more artistic than myself to come up with a design. “Stop Global Warming: Snuff the Sun.”
Those replies are frightening
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