Do you understand long-term trends and how they're important to science?
A lot of denialists seem to be unclear about certain basic things about how science works. Specifically, they seem to misunderstand uncertainty, long-term trends, statistical significance, and the peer review process. I'll be asking about each of them in separate questions.
As I understand it, a reasonable short description of long-term trends and their importance to science:
Scientific theories often deal with ideal situations--ones where only the force or detail you're interested in changes. For example, an object in motion will stay in motion without any further force only in a frictionless environment. The real world is generally a lot more messy. But, data noise (the random variations in data from things like friction, uneven materials, and the like) will be reduced or eliminated if you have a sufficiently large data set--for example, by looking at a world-wide trend for many years vs looking at conditions in a limited area for a few years--since random variations will tend to cancel each other out. The more "noise" you have, the larger the data set you need to find the true trend in a set of data. And climate is very "noisy", so we need big data sets to figure out what's really going on.
Additionally, specific to climate science, there are several aspects of climate that are known to be cycles of varying length. The shorter the time span you're looking at, the more likely you are to have only one part of some long cycle, and thus have a picture distorted by the changes caused by that phase of the cycle.
So. 1. do you have any disagreements about my gloss of how long-term trends work? If not, please offer any necessary corrections. 2. Do you understand long-term trends, and how they're important to science, at least in broad terms? 3. Do you accept, have reservations about, or reject the scientific consensus on AGW? (that is, that temperatures are rising, it's primarily due to human emissions of greenhouse gasses, and it's likely to cause problems)
Anonymous2012-07-15T14:41:37Z
Favorite Answer
Consider the issue of when the next geomagnetic reversal will occur. Earth's magnetic field strengthened between 1800-1900 and weakened between 1900-1995. http://www.nationalatlas.gov/articles/geology/a_geomag.html
Does this mean that Earth is due for a polarity reversal? The answer to that question depends on whether the past behavior of Earth's magnetic field. If such single century decline of the strength of Earth's magnetic field strength has been common tens of thousands of years prior to such polarity reversals, the answer is probably no. If such single century decline of the strength of Earth's magnetic field strength almost always continues until a polarity reversal happens, then the answer is probably yes.
Regarding global warming; yes, it is happening http://www.noaanews.noaa.gov/stories2010/images/warmingindicators.jpg And we are causing it http://planetsave.com/2010/08/18/humans-cause-global-warming-10-indicators/
The ten warmest years in the instrumental record are 2010, 2005, 2009, 2007, 2002, 1998, 2006, 2003, 2004 and 2011. http://data.giss.nasa.gov/
Maxxbush
<<A lot of denialists seem to be unclear about certain basic things about how science works. > <I disagree. We true scientists do know about science.>
LOL! When you answer a question, you almost always post quotations from politicians, such as Michail Gorbachev, and almost never link to peer reviewed research or tabular or graphical data. Such answers are what we call "ad hominem arguments." http://dictionary.reference.com/browse/ad+hominem
Yes, I understand long-term trends and how they are important to science-to a certain extent.
First, let me outline my limitations-I'm very good at analysis and logic; I can look at a business and indentify potential and problems with pinpoint accuracy based on the numbers, but climate science is outside of my field and statistics is not my strong point. So when I look at long term trends and the statistical probabilities that they indicate it is difficult for me to interpret how the conclusions got from point A to point B. It would be helpful for me-and I know I am not alone-to know more about the computer modeling used and the specific variables that were included. I also have some limitations when it comes to reading peer-reviewed publications, primarily in terms of vocabulary, although also some issues with knowledge of processes; for example, when I first ran across the term 'albedo' it took a while to figure out what they were talking about; I also struggle with understanding the effects of thermohaline circulation. So I often have to rely on interpretations by others, and since those reports are so frequently shaded by political or other agendas it can be hard to go back to the actual research and sort out. Finally, there is a lot of mis or disinformation that is repeated so often it can be confusing, I often gloss over the errors and outright lies initially and then go 'wait a minute...' later. Which is what I suspect the disseminators of disinformation have in mind when they publish it to begin with, except they hope people won't have the 'wait a minute' moment. For a simple and non-scientific example, in 'the Great Global Warming Swindle' there is a segment about a medical clinic that is inadequately powered by solar and how this alternative source of energy is a boondoggle because conventional power would supply plenty of electricity to operate the facility at lower cost. At first blush, this makes sense; but when you think about the time and expense to build a power grid to supply places like this clinic, the obvious solution is to add more solar panels. The 'disinformation' is obviously the clear omission of how difficult, costly and time consuming it would be to get the grid built to deliver power to remote areas like this...and how it would be funded. So you can see that the 'business' side of the equation comes easily to me in terms of the cost and benefit analysis. The clinic needs more power now, so dismissing solar when it will take years of work and billions of dollars to construct a grid when another solar panel can be installed and delivering the additional electricity in a matter of days is just stupid. Find the funding for it, buy the necessary panels, and get them installed.
Second, what really constitutes a long-term trend, and is it weather or climate? For example, we see a historic period of cooling over several decades and it is ascribed to particulate emissions, or a shorter term trend that is impacted by El Nino and La Nina events. I'm uneasy with some of the conclusions reached based on time periods that are affected by variables such as these, and at this juncture don't see 30-40 years periods as long term enough to be conclusive. I understand the limitations of research and availability of data, but I am not well enough attuned to what constitutes long-term trends in terms of scientific conclusions.
So my answers to your followup questions in the context I have just provided: 1. I do not have any disagreements with the general concept of how long-term trends work. 2. I understand long-term trends at least in broad terms, but am uncertain insofar as what really constitutes a 'long term' trend from which conclusions can be reached about climate. 3. I accept the consensus of science because I do not have the necessary information or expertise to reject it, with the following notations: a) I accept that global average temperatures are rising. b) I accept that human emissions of greenhouse gasses influence climate, but need more information to understand how much. c) I accept that climate change is likely to cause problems but am uncertain about the nature, extent and timing of the problems.
I believe the key to the overall conclusions that may be drawn from my answer is in the three notations (a, b & c) above; these factors prevent me from supporting policies that may have geopolitical and economic impacts based solely on the conclusions and consensus to date about human emissions of greenhouse gasses.
1. The Earth has existed for billions of years. We have temperature records for about 100 years. We can look back farther and guess what the climate was like. 2. Yes. 3. In the past, there was a scientific consensus that the Earth was flat. It was partially driven by religious leaders, similar to how Al Gore has lead the consensus about AWG. We all see how the flat Earth consensus turned out.
Long term trends certainly are important to CLIMATE CHANGE science.
Long term trends are less important, but still important, in politics. Hard to say if anti-science denial of climate science is a long term trend (like denial of evolution) with political staying power or a short term delusion (like believing that neo-cons were consistent, convincing, informed, competent, and to be cringed down to).
Edit: I have posted a link to "the owner is climate, the dog is the weather" video here a few times. First learned of it on realclimate.org. Here's the direct link to u-toob: http://www.youtube.com/watch?v=e0vj-0imOLw&feature=youtu.be
Someone recently posted this animation which I think brilliantly illustrates trends vs year-to-year variations. Thank you to whoever it was, sorry I forgot who it was, and I only saw it because you linked it.