# Confirmation of Climate change - observable by human senses ? **URL:** \ **Category:** Factual Questions\ **Created:** [April 4, 2018, 2:18pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807 "2018-04-04T14:18:59Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![am77494](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@am77494](https://boards.straightdope.com/u/am77494)\ **Post date:** [April 4, 2018, 8:55pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/21 "2018-04-04T20:55:17Z")
> [@Exapno\_Mapcase](#): > > An individual event is a data point. Statistics combines data points to test whether they are collectively meaningful or over time point to longer-term trends. The difference is critical. > > For a simplified example: The average temperature for a particular day at a given spot is a data point. The movement of the average temperature over time provides statistical meaning to statements about change in that period. The collection of all average temperature for all spots over time is the basis for understanding climate change. Good points Expanso. I was trying to be not pedantic and Colibri answered my question satisfactorily above. I was trying to see if there was confirmation bias present in our current observation of weather events. It looks like you are a Statistics Guru, so maybe I should have phrased the question to you as “ If I take the average daily temperature of Oklahoma City for 2008-2018 and do a T-test against the same data for 1908-1918, what will be the outcome ?” Maybe that’s not the correct question either. The main lesson from the above discussion for me is that local weather events and short term weather effects do not prove or disprove Climate change. At the individual level (unless you are observing glaciers or sea levels or animal migration) you will not observe Climate change at a statistically significant level. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 4, 2018, 9:01pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/22 "2018-04-04T21:01:26Z")
Of course, a glacier or the sea level isn’t an individual event. It’s the cumulative result of many, many events, over the course of years or longer. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [April 4, 2018, 9:27pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/23 "2018-04-04T21:27:51Z")
> [@am77494](#): > > At the individual level (unless you are observing glaciers or sea levels or animal migration … …or [coral reefs](https://oceanservice.noaa.gov/facts/coralreef-climate.html), or [animal & plant extinctions](http://www.climatechangenews.com/2016/12/20/global-warming-linked-to-plant-animal-extinctions/), or [plant hardiness zones](https://www.washingtonpost.com/blogs/capital-weather-gang/post/new-usda-plant-zones-clearly-show-climate-change/2012/01/27/gIQA7Vz2VQ_blog.html?utm_term=.444a3c2cd812), or [arctic sea ice](https://blogs.agu.org/wildwildscience/2015/09/04/the-great-polar-melt-continues/), etc… ---
**Author:** ![snowthx](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowthx/32/10660_2.png) [@snowthx](https://boards.straightdope.com/u/snowthx)\ **Post date:** [April 4, 2018, 9:33pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/24 "2018-04-04T21:33:24Z")
Observable by human senses? A couple come to mind: I moved to the Sacramento area about 19 years ago. I remember great [tule fog](https://en.wikipedia.org/wiki/Tule_fog) banks during winter. Sometimes you would not see the sun for days. People in the higher-elevation Sierra foothills like to brag “Below the snow, above the fog.” However, for the last maybe 8-10 years, very few week-long winter fogs. In fact hardly any days-long fog events. Maybe there are some stats on the decline of fog-related traffic accidents in the Sac-Joaquin valleys in recent years? I went to Mexico in 2004 and observed these noisy and showy black birds with an almost electric sounding array of calls, the [Mexican Grackle](https://en.wikipedia.org/wiki/Great-tailed_grackle). I had never seen or heard one of these before. Today, they patrol parking lots everywhere in my area. Perhaps these birds have made a recent northern push? ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [April 4, 2018, 9:48pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/25 "2018-04-04T21:48:13Z")
> [@snowthx](#): > > I went to Mexico in 2004 and observed these noisy and showy black birds with an almost electric sounding array of calls, the [Mexican Grackle](https://en.wikipedia.org/wiki/Great-tailed_grackle). I had never seen or heard one of these before. Today, they patrol parking lots everywhere in my area. Perhaps these birds have made a recent northern push? Great-tailed Grackles (the official name of the “Mexican Grackle”) have indeed been [expanding their range northward in recent years](https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2699.2003.00970.x), especially in the west. However, part of this is their expansion into human-modified environments. > [@](#): > > Between 1880 and 2000 the great‐tailed grackle expanded its breeding range in the USA from c. 64,000 km2 to more than 3,561,000 km2, an increase of 5530%. The average annual rate of increase is 3.4%, but has lessened during the past 20 years. Northward movement in the eastern portion of the range has slowed down, reflecting this decrease. However, in the central and western portion of the species range, the rate of northward movement is still accelerating. Northern Mockingbirds were unheard of in the New York City region when I was growing up in the 1950s. Now they are very common. Other species have experienced similar range expansion northward. ---
**Author:** ![am77494](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@am77494](https://boards.straightdope.com/u/am77494)\ **Post date:** [April 4, 2018, 10:11pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/26 "2018-04-04T22:11:55Z")
> [@Colibri](#): > > Northern Mockingbirds were unheard of in the New York City region when I was growing up in the 1950s. Now they are very common. Other species have experienced similar range expansion northward. Colibri - I am not doubting your account or Climate change. I am questioning if observations such as this one on Mockingbirds has some degree of confirmation bias associated with it. Can we say certainty ( with reasonable p number) that the Mockingbird’s range expansion is Caused by climate change. Or is this just a correlation and maybe there are other factors at play like it’s natural habitat destruction or urban shelters or urban food availability etc ? ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [April 4, 2018, 10:23pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/27 "2018-04-04T22:23:28Z")
> [@am77494](#): > > I am questioning if observations such as this one on Mockingbirds has some degree of confirmation bias associated with it. Can we say certainty ( with reasonable p number) that the Mockingbird’s range expansion is Caused by climate change. Or is this just a correlation and maybe there are other factors at play like it’s natural habitat destruction or urban shelters or urban food availability etc ? To continue the point we have been trying to make, single observations or observations of single species don’t prove anything. But when you see the same kind of correlated range expansions northwards in dozens of species that confirms the pattern. Science consists of testing falsifiable hypotheses. So it could be tested whether the northward expansion is correlated with increased temperatures or other factors such as urbanization. [Here’s an example of testing a whole bird community.](https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.12740) > [@](#): > > Using data from Project FeederWatch, an international citizen science program, we quantified spatiotemporal changes in winter bird communities (n = 38 bird species) across eastern North America and tested the influence of changes in winter minimum temperature over a 22‐year period. We implemented a jackknife analysis to identify those species most influential in driving changes at the community level and the population dynamics (e.g., extinction or colonization) responsible for these community changes. Since 1990, we found that the winter bird community structure has changed with communities increasingly composed of warm‐adapted species. This reshuffling of winter bird communities was strongest in southerly latitudes and driven primarily by local increases in abundance and regional patterns of colonization by southerly birds. CTI tracked patterns of changing winter temperature at different temporal scales ranging from 1 to 35 years. We conclude that a shifting winter climate has provided an opportunity for smaller, southerly distributed species to colonize new regions and promote the formation of unique winter bird assemblages throughout eastern North America. There are large numbers of studies of this kind confirming these trends. ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [April 4, 2018, 10:51pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/28 "2018-04-04T22:51:16Z")
The Dept. of Agricultural charts [plant hardiness zones](https://www.arborday.org/media/mapchanges.cfm), which are basically charts of the average annual lowest temperatures in winter. Tracking the changes from 1990-2016, [the zones east of the Rocky Mountains are moving northward,](https://www.arborday.org/media/mapchanges.cfm) i.e., the coldest winter temperatures are getting warmer than they used to be. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [April 4, 2018, 11:37pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/29 "2018-04-04T23:37:47Z")
Opening of the Northwest passage is a pretty good indication. Even in the 1970s a Swiss told me that the Rhone glacier had retreated from 2000 m to 3000 m in the last century. I wonder where it is now 40 years later. ---
**Author:** ![RadicalPi](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/radicalpi/32/9806_2.png) [@RadicalPi](https://boards.straightdope.com/u/RadicalPi)\ **Post date:** [April 5, 2018, 12:01am UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/30 "2018-04-05T00:01:59Z")
There is something like XKCD this perhaps. > **[Cold](https://xkcd.com/1321/)** > > 'You see the same pattern all over. Take Detroit--' 'Hold on. Why do you know all these statistics offhand?' 'Oh, um, no idea. I definitely spend my evenings hanging out with friends, and not curating a REALLY NEAT database of temperature statistics. Because, pshh, who would want to do that, right? Also, snowfall records.' ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [April 5, 2018, 1:40am UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/31 "2018-04-05T01:40:31Z")
> [@RadicalPi](#): > > There is something like XKCD this perhaps. > > [xkcd: Cold](https://xkcd.com/1321/) Not unlike Post #5. ---
**Author:** ![Mr.Duality](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mr.duality/32/4098_2.png) [@Mr.Duality](https://boards.straightdope.com/u/Mr.Duality)\ **Post date:** [April 5, 2018, 2:31am UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/32 "2018-04-05T02:31:15Z")
Related to plant hardiness zones: We don’t see maple syrup produced in USA anymore. It’s all from Canada because the US is now too warm for Sugar Maple Trees. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [April 5, 2018, 3:24am UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/33 "2018-04-05T03:24:08Z")
> [@am77494](#): > > What’s with the snarky response ? As I understood the thermometers used in Climate change research have two to three decimals of significant digits. Or are they common household thermometers ? > [@am77494](#): > > Cite please ? Whenever I have used mercury thermometers for high resolution, I have found them limited to a resolution to about 0.05C. And they have to be read in conjunction with a correction curve that accounts for the manufacturing variability in the bulb/capillary. It’s nothing like a household thermometer. Air temperature measurement collected by NOAA have a precision of ±1ºF {“Table 4.1. Performance Standards – Air Temperature Measurements.” on page 7 of this PDF file} … That’s close enough for government work … it can be 2ºF different just a quarter mile away … so any higher precision doesn’t really give us any new information … it’s expensive laying out a network of weather stations and we have to leave them out in the weather … installing and maintenance of these stations fall on NOAA’s shoulders and all the other research and civilian interests just use that set of data … Averaging temperatures over years gives us a number … we have to remember that any specific temperature reading may be far away from this average temperature, what would be called a large standard deviation … what ever else is said of this, a few degrees either way on the daily measurements (or hourly) isn’t changing the warming tread over these past 100 years … I agree with **Colibri** … the intense biological reaction to even small changes is pretty obvious year-to-year … and certainly decade-to-decade … ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [April 5, 2018, 3:45am UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/34 "2018-04-05T03:45:51Z")
> [@am77494](#): > > Or is this just a correlation and maybe there are other factors at play like it’s natural habitat destruction or urban shelters or urban food availability etc ? This is easily studied and of course has been. It is again the difference between individual data points and statistical correlation. Many, many different results in many, many different fields observed at many, many different places all correlate with global warming and the effects that can be predicted to have in specific localities. Correlation is not causation, as everybody will quickly say. The problem with writing all these patterns off is the utter lack of any other known cause that can account for them. Other explanations have of course been examined, from the logical - increased solar radiation - to the pseudoscientific - increased heat from the earth’s core. None produced the required correlations. That’s also an important point. Correlations must exist with any postulated cause, and those can be predicted through models. Our models are not perfect and neither is our data but at this moment nothing is a plausible replacement for the effects of CO2 and the other greenhouse gases. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [April 5, 2018, 12:09pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/35 "2018-04-05T12:09:14Z")
> [@Mr.Duality](#): > > Related to plant hardiness zones: > > We don’t see maple syrup produced in USA anymore. It’s all from Canada because the US is now too warm for Sugar Maple Trees. Wrong. This year, maple syrup production in Wisconsin will be higher than ever, since the daily warm/cold cycle has been extremely favorable (below freezing at night, above during day). The trees all have collection bags or pails right now, and some are connected with hoses to a large tank. [Jorn’s Sugar Bush](http://www.jornssugarbush.com/) [Here’s a video I made about 9 years ago about local syrup making.](https://youtu.be/RvC8P1ntut4) Maple syrup is made in 13 states, led by Vermont. USA production has increased about 30% from 2015 to 2017. [USA production figures](https://www.nass.usda.gov/Statistics_by_State/New_York/Publications/Latest_Releases/2017/2017_Maple_Syrup.pdf) ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [April 5, 2018, 1:33pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/36 "2018-04-05T13:33:41Z")
> [@Exapno\_Mapcase](#): > > [snip] … Our models are not perfect and neither is our data but at this moment nothing is a plausible replacement for the effects of CO2 and the other greenhouse gases. Also deforestation … These two causes are things humans can do something about … and so certainly should … Arbor Day is April 27th this year … plant a tree will’ya? … ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [April 5, 2018, 1:40pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/37 "2018-04-05T13:40:53Z")
> [@Exapno\_Mapcase](#): > > Many, many different results in many, many different fields observed at many, many different places all correlate with global warming and the effects that can be predicted to have in specific localities. See [consilience:](https://en.wikipedia.org/wiki/Consilience) > [@Wikipedia](#): > > Because of consilience, the strength of evidence for any particular conclusion is related to how many independent methods are supporting the conclusion, as well as how different these methods are. Those techniques with the fewest (or no) shared characteristics provide the strongest consilience and result in the strongest conclusions. This also means that confidence is usually strongest when considering evidence from different fields, because the techniques are usually very different. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 5, 2018, 1:48pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/38 "2018-04-05T13:48:28Z")
Plus, if anthropogenic carbon dioxide weren’t causing warming, we’d have to ask why not. We know how carbon dioxide interacts with infrared from laboratory experiments, we know how much carbon dioxide is in the atmosphere, we know how much of it humans are producing. The increase in the amount in the atmosphere matches the amount we’re producing, and the greenhouse effect one would expect from that amount of carbon dioxide matches the warming we observe. For the warming to not be anthropogenic, we’d have to assume that something is preventing the carbon dioxide from producing a greenhouse effect, and that at the same time some other completely unrelated natural phenomenon is causing the warming we’re observing. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [April 5, 2018, 2:28pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/39 "2018-04-05T14:28:51Z")
> [@Chronos](#): > > [snip] … The increase in the amount in the atmosphere matches the amount we’re producing … [snap] Not to hijack, but I’d love to see your math that supports this claim … ---
**Author:** ![GIGObuster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gigobuster/32/421_2.png) [@GIGObuster](https://boards.straightdope.com/u/GIGObuster)\ **Post date:** [April 5, 2018, 2:46pm UTC](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807/40 "2018-04-05T14:46:04Z")
> [@watchwolf49](#): > > Not to hijack, but I’d love to see your math that supports this claim … > **[How Do We Know that Humans Are the Major Cause of Global Warming?](https://www.ucsusa.org/resources/are-humans-major-cause-global-warming)** > > A straightforward explanation of how we know that humans cause global warming, using charts, graphs, and plain language. > [@](#): > > We know human activities are driving the increase in CO2 concentrations because atmospheric CO2 contains information about its source. Scientists can tease apart how much CO2 comes from natural sources, and how much comes from combusted fossil fuel sources. > > Compared to other carbon sources, carbon from fossil fuels has a distinctly different “signature,” essentially the relative amount of heavier or lighter atoms of carbon (technically δ13C). The more negative the δ13C, the higher the proportion of carbon from fossil fuels. > > Over the years, δ13C has decreased while the overall amount of CO2 has increased. This information tells scientists that fossil fuel emissions are the largest contributor of CO2 concentrations since the pre-industrial era. > **[RealClimate: How do we know that recent CO2 increases are due to human...](https://www.realclimate.org/index.php/archives/2004/12/how-do-we-know-that-recent-cosub2sub-increases-are-due-to-human-activities-updated/)** > > RealClimate: Note:This is an update to an earlier post, which many found to be too technical. The original, and a series of comments on it, can be found here. See also a more recent post here for an even less technical discussion. Over the last 150... > [@](#): > > Over the last 150 years, carbon dioxide (CO2) concentrations have risen from 280 to nearly 380 parts per million (ppm). The fact that this is due virtually entirely to human activities is so well established that one rarely sees it questioned. Yet it is quite reasonable to ask how we know this. > > One way that we know that human activities are responsible for the increased CO2 is simply by looking at historical records of human activities. Since the industrial revolution, we have been burning fossil fuels and clearing and burning forested land at an unprecedented rate, and these processes convert organic carbon into CO2. Careful accounting of the amount of fossil fuel that has been extracted and combusted, and how much land clearing has occurred, shows that we have produced far more CO2 than now remains in the atmosphere. The roughly 500 billion metric tons of carbon we have produced is enough to have raised the atmospheric concentration of CO2 to nearly 500 ppm. The concentrations have not reached that level because the ocean and the terrestrial biosphere have the capacity to absorb some of the CO2 we produce.\* However, it is the fact that we produce CO2 faster than the ocean and biosphere can absorb it that explains the observed increase. > > Another, quite independent way that we know that fossil fuel burning and land clearing specifically are responsible for the increase in CO2 in the last 150 years is through the measurement of carbon isotopes. Isotopes are simply different atoms with the same chemical behavior (isotope means “same type”) but with different masses. Carbon is composed of three different isotopes, 14C, 13C and 12C. 12C is the most common. 13C is about 1% of the total. 14C accounts for only about 1 in 1 trillion carbon atoms. > [@](#): > > For those who are interested in the details, some relevant references are: > Stuiver, M., Burk, R. L. and Quay, P. D. 1984. 13C/12C ratios and the transfer of biospheric carbon to the atmosphere. J. Geophys. Res. 89, 11,731-11,748. > Francey, R.J., Allison, C.E., Etheridge, D.M., Trudinger, C.M., Enting, I.G., Leuenberger, M., Langenfelds, R.L., Michel, E., Steele, L.P., 1999. A 1000-year high precision record of d13Cin atmospheric CO2. Tellus 51B, 170–193. > Quay, P.D., B. Tilbrook, C.S. Wong. Oceanic uptake of fossil fuel CO2: carbon-13 evidence. Science 256 (1992), 74-79 [Previous page](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807.md?page=1) [Next page](https://boards.straightdope.com/t/confirmation-of-climate-change-observable-by-human-senses/811807.md?page=3)