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The Heat is On: U.S. Temperature Trends

Research Report by Climate Central

Report Summary

Global warming isn't uniform. The continental U.S. has warmed by about 1.3°F over the past 100 years, but the temperature increase hasn’t been the same everywhere: some places have warmed more than others, some less, and some not much at all. Natural variability explains some of the differences, and air pollution with fine aerosols screening incoming solar radiation could also be a factor.


Our state-by-state analysis of warming over the past 100 years shows where it warmed the most and where it warmed the least. We found that no matter how much or how little a given state warmed over that 100-year period, the pace of warming in all regions accelerated dramatically starting in the 1970s, coinciding with the time when the effect of greenhouse gases began to overwhelm the other natural and human influences on climate at the global and continental scales.

We looked at average daily temperatures for the continental 48 states from 1912 to the present, and also from 1970 to the present and found:

  • Over the past 100 years, the top 10 states warmed 60 times faster than the bottom 10 (0.26°F per decade vs. 0.004°F per decade), when looking at average mean temperatures. During this timeframe, 45 states showed warming trends, although 21 were not statistically significant. Three states experienced a slight cooling trend.
  • Since 1970, warming began accelerating everywhere. The speed of warming across the lower 48 more than tripled, from 0.127°F per decade over the 100-year period, to 0.435°F per decade since 1970, while the gap between the fast and slowly warming states narrowed significantly; the 10 fastest warming states heated up just twice as fast, not 60 times as fast as the 10 slowest warming states (0.60°F vs. 0.30°F per decade). Over the past 42 years 17 states warmed more than half a degree F per decade.
  • The states that have warmed the most — whether you look at the past 100 years or just the past 40 — include northern-tier states from Minnesota to Maine and the Southwest, particularly Arizona and New Mexico. Places that have warmed the least include Southeast states, like Florida, Alabama, Georgia and South Carolina, along with parts of the central Midwest, like Iowa and Nebraska.


By John Rundall (98199)
on June 13th, 2012

This first map (after 1970) is very compelling - showing the change per decade over the past 4 decades (more or less).  It is all yellow or 0.2 deg/decade or moreand there is no green or blue.

Comparing it with the other map is worthless because the second map shows the change per decade over the last 100 years, including the past 40!  You then make the point that temperature increases are “accelerating” but the point is diluted because you include the most recent 40 years rates.  It would be much more compelling to show the average increase per decade from 1912 to 1970 so one could really compare the two average rates.  Combining them in one map (1912-2011) just muddles the issue.

The other problem with the 1912-2011 map is that is shows that over the long run - and for many areas (notably the SW and the NW or the green areas) there is NO warming, so it really seems to miss the mark.  Ironically, for someone who is genuinely concerned about global warming, the 1912 to 2011 makes me say - it doesn’t look that bad so why worry.

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By Mary Hiebl (53146)
on June 14th, 2012

This is a scientifically serious issue which cannot be denied or overlooked.  What’s the game plan for decelerating and diminishing this trend?

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By Sally Mills (Eden Prairie, MN, 55344)
on June 15th, 2012

John, I agree that a map showing the change from 1912 to 1970 would be helpful - it would be interesting to see the change over those 60 years, and then compare it to the change over the last 40 years.

I suspect we would see that the temperature changes were minor in the first 60 years and accelerated in the last 40 years.  That prompts the question, if the temperature increases are accelerating now and they accelerate even more in the future, what will happen? How hot will it get?

I lived in Minnesota from 1971 to 1975.  Literally all winter it was 10 degrees below zero F, except for two weeks when it was 20-30 below zero F. 

Over the last 3 winters, there were a few days below -10F, but mostly it was in the +20s.  This past winter here was almost no snow.  This map seems to match my experience in Minnesota!

Let’s get started on stabilizing our climate!

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By Lindsey Stanford (Oklahoma City, Ok. 73115)
on June 15th, 2012

I have serious concerns about climate change and overall impact of human behavior on the earth..  However, this report has caused me great confusion.  If the maximum change by state in the last 10 years is .339 per decade and the highest rate since 1970 is .639 per decade how could the temperature have risen by 1.3 degrees overall?

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By Michael T (Sophia, NC, 27350)
on June 15th, 2012

The data used in this report can also be found in NOAA’s State of the Climate Report:

Also from NOAA’s U.S. Climate at a Glance page:

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By Joseph Marshall (Columbus OH, 43214)
on June 15th, 2012

While all these statistics are impressive, as can be seen, there is always some way to disparage them.  What cannot be denied, and is the real reason why climate change is important, is the directly observed effects on the biosphere.  My parents grew roses and chrysanthemums for exhibition from 1956 to 1986 as well as making an extensive planting of Spring ornamentals at a new home from 1963-1965.  All of these are subject to significant damage by hard freezing, and much of my family’s life revolved around the dates of killing frosts.  I can attest in my region true killing frosts have all but vanished in the crucial period of mid-March to mid-May and mid-October to mid-November resulting in a functional increase of 2-3 weeks in the ornamental growing season in both spring and fall.  The most dramatic effect which anyone with eyes, a memory, and mind could see was in the sequence of spring ornamental trees.  They once had a distinct sequence based on the frost cycle:  forsythia, star magnolia, southern magnolia, pear, crabapple, cherry, true apple, lilacs, and dogwood, extending from mid-March to mid-May.  All of them now bloom at once during the first three weeks in April! 

Why is this important?  Consider an America that no longer grows significant feed corn and soybeans to feed cattle and hogs and a Canada which now can.  Which one of them would have a significant decrease in the standard of living?  When will this happen?  I have no idea.  But it will happen if the climate continues to warm. 

With one exception, most of these numbers have little immediate effect on humankind that can be directly seen.  But mean low maximum temperature does.  It determines what plants winter over.  Period.  The USDA hardiness zone map, based, I believe, on data up to the early to middle 1960’s claims that my county has a mean low winter temperature range of -5 deg F to -10 deg F.  Temperatures below 0 deg F have vanished in this region completely.  2010-2011 was “the coldest winter since the blizzard of 1975-1976” based on average daytime temperature.  The absolute low temperature in that year was -16 deg F, the absolute low of 2010-11 was +4 deg F!  In 1975-76 entire species of widely planted ornamentals were totally destroyed, most notably the bright orange fall berries of pyracantha.  In 2010-11 the biosphere of ornamentals hardly noticed.  The mass bloom was delayed about a week.

On the level of plant and animal life these are massive and perfectly visible changes.  That is if you stick your nose out the door to do anything but drive to and from work.  These days there is far too much number crunching and far too little direct observation in science as a whole.  Out in the elements the verdict is in.  The climate is changing.  Fast.  Sixty odd year old farmers, hunters, bird watchers, gardeners, and nurserymen are watching it.  Numbers are nice, but you have to know which ones count before you start arguing about them.

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By Craig Dillon (Chicago, IL 60607)
on December 21st, 2013

I agree with you. In Chicago, Lake Michigan is now a warm lake in the summer. It did not used to be that way. Even in a hot summer, it would be teeth chattering cold. Now, it is piss warm in the summer. No discomfort at all. It feels like I am swimming off the Florida Keys. Also, we used to get ice on Lake Michigan that required an ice breaker each spring to open up the shipping channel for the St. Lawrence Seaway. Not any more. The lake is too warm to freeze over.

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By chums
on June 16th, 2012

the plan is to eat the hungry people and cut down all the trees so the earth is more reflective!  the plan is to spray metal oxides in the air to block the sun’s rays! ironically they are planning spraying-  while actual spraying has gone on since the late nineties, and monsanto already has an aluminum resistant papaya seed.  what a coincidence!  what i am saying can all be substantiated except the part about eating the hungry.  oh and this is a fact as well,
less than 20 cargo ships carrying cheap goods from china outpollute all of the cars on the entire planet.  so if you want to curb something, curb your consumption and quit living in fear about uncontrollable CO2 in the atmosphere.

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By Ursus Ameicanus (Northport Al 35473)
on June 17th, 2012

That map lies by omission. While it claims an overall warming trend from 1970 to 2011 in the US, it doesn’t address a similar trend from c. 1905 until c. 1935, and a cooling/leveling trend from c. 1935 until c. 1970. It also doesn’t show little, if any net warming from 1895 to 2010, and that we’re potentially moving into another another cooling trend.

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By Joseph Marshall (Columbus, OH 43214)
on June 18th, 2012

This business of what numbers to look at could be expanded a bit for those who might want to dig into the original data.  The key temperatures are as follows:  the minimum absolute low temperature ( discussed above ),  the number of days of daytime high temperatures continuously below the freezing point of water of 32 deg F,  the number of days of continuous daytime high temperatures above 86 deg. F, and the number of days of continuous nighttime low temperatures above 50 deg. F.

Changes in any of these four will produce very clear and unequivocal changes in the biosphere.  Frozen streams and ponds will force migrating waterfowl further south for unfrozen water in which to swim.  Significant changes in local migratory behavior and numbers is an indicator of permanent changes in the number of frozen water days.  In my region, all common waterfowl migrated further south during the coldest part of the winter.  About 1995 Canada geese and Mallard ducks started wintering over in my county, when they never had before—the coldest winters will drive them away from here, but, more often than not, they now stay.  This is also beginning to happen to migratory song birds such as Robins, who must have unfrozen water to drink.  They, too, now routinely winter over here where they did not before.  Good data of this kind is usually kept by local birding clubs.

Most ornamental annuals and perennials will stop growing and go dormant with daytime highs above 86 deg. F.  If the continuous hot weather lasts long enough such plants will die no matter how much you water them.  Changes in this variable will be reflected in the types of species that will survive the Summer.  Pansies are a good test plant here.  In hotter summers they will die completely, in the milder ones they will return to bloom a second time in the Fall.  This has become less common here than it was in the past.

Plants such as peppers and tomatoes will not grow when the nighttime lows are below 50-55 deg. F, and they will not set fruit until the daylight lasts long enough.  Even if tomatoes are not setting in the fall, the fruits will continue to slowly ripen until the first hard freeze of about 25 deg. F..  A common Fall dish here among vegetable gardeners used to be fried green tomatoes, because the vines were still laden with green fruit at the hard frost.  The hard freeze date is now so late here that leftover green tomatoes have vanished—every fruit a plant sets now has time to ripen.  Another test for this is the ripening of rose hips.

Anecdotal data of this type can be found in most places, as can actual temperature records.  We rely too much on global data to make the case for climate change.  Far more unimpeachable data exists in local biospheres, and if you search for data in enough of them the overall results would be unequivocal:  a plant dies or it lives, a bird migrates or remains, a fruit ripens or fails to, and plants start their growth earlier or later.

This should be enough to convince the reasonable.  As always the unreasonable are the unreachable.

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By david grondin (04463)
on June 24th, 2012

really like the info

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By CharlesKayeMBA (Cave Creek/AZ/85331)
on June 25th, 2012

100 year data shows little to no increase in the majority of the US. (Alabama seems to cool off… Interesting)

The 40 year data, which is comprised of a smaller data set, and is therefore statistically less accurate, shows what you want to show, so you lead off with that map.

No mention of global data and a map thereof. Why not? Does it not coincide with your agenda? Where is Alaska and HI?

No mention of the increase in recorded temps attributable to urban expansion and the materials used to build our cities which absorb more IR energy than the natural environment, thereby increasing recorded temps. This fact is always ignored by those presenting temperature data. I wonder why?

If your intent was to cherry-pick data to show your agenda, you’ve done a great job. If your intent was to honestly represent statistical data, then you get an “F”.

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By David (Sunny California)
on June 25th, 2012

This temperature tracking data is like a bathing suit, what i shows in interesting but what it conceals is crucial. Much of the data gathered is from stations not following NOAA’s own guildlines for the placement of said stations. Check out this link.

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By BadMap
on June 25th, 2012

So why does it drop so much when I cross an imaginary political line. Charts like this are poorly conceived. What you really have is big blobs of red warming in the midwest and the southwest, interspersed with some steep gradients in areas where warming trends haven’t accelerated so much (assuming your data source isn’t also completely corrupted by your unknown analytical abilities) ... by the time you explain that the map isn’t REALLY a chart of temperature change vs. geographic position, you’ve lost your audience that really doesn’t care and now thinks you’re dishonest. And you are. The temperature DID NOT change that much in Mankado, because your measurement wasn’t MADE THERE. Why did you color it in??

This would be better represented as a bar graph with states on one axis and change on the other, and ranked by magnitude. At least then you aren’t implying that I can walk across an imaginary line and suddenly I’m in a different region with a phenomenally different warming pattern. “Please people, this is serious, look at this chart that I’ve made grievous errors in presentation on - but I can be trusted with the really important stuff”.

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By Bill Sundling (Neenah, WI 54956)
on June 27th, 2012

The concept of man-made climate change is a complete and total fraud. Climate change is a religious industry where only true believers are accepted, data is deliberately skewed, and where heretics are persecuted. Seriously, after the climategate emails were released how can anyone take it seriously?

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By David (Denver)
on July 18th, 2014

Assume the man-made part is a hoax. The warming is still happening, and it can be proven that by lessening the CO2 output of humans we can slow the rate. So the question for you is this: Should we clean out the water bowl, or keep peeing in it?

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By Gordon Graham (Mukilteo, WA 98275)
on July 4th, 2012

Before Gore’s “Inconvenient Truth,” there was the BBC’s 1989 program called: “After the Warming.” Before that, in 1972 there was “Limits To Growth.” Those folks from M.I.T. who wrote LTG weren’t worried about global climate.  They were worried about what is now called “the poisoning of the planet.” Before March 2011, that was mostly air pollution. Since the earthquake & tsunami at Fukushima, a new, even more deadly set of chemicals, have been trickling out to the rest of the world.  If you follow, the possibility of further radioactive release - due to the collapse of some of the storage buildings - has emerged.  Depending on whose hype and hysteria you monitor, another earthquake stronger than the one last week or a typhoon/hurricane stronger than the one a couple of weeks ago, all of which are highly likely, eventually, will topple those buildings before the problem might be rectified - ten years from now at the earliest.  After that, global warming will be no big deal.

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By Shannon McNeeley (80304)
on July 4th, 2012

I’m sure the report says this (which I haven’t read yet), but this map does not include Alaska (or Hawaii), so keep in mind the rankings would all be at least one place lower if you included Alaska since Alaska has warmed the fastest of any U.S. state, so would be #1 instead of Arizona. I’m not sure where Hawaii falls, but it would also change the rankings at some point.

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By Aiyana (tinley park/IL/60477)
on July 6th, 2012

Nature is a living entity…and like all living entities it will cure itself to survive… this case humans are the cancer…....sure they may survive….but they will CURED first.

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By Dorothy Daughter (Redding CA 96001)
on July 8th, 2012

Mr. Sunding is a blabbering idiot. There is no evidence of skewed data, in fact, peer reviewed scientific literature reveals a careful approach to published facts and reports.  The climategate emails were thoroughly investigated 3 times, no flawed data or results were found (and Mann was exonerated, all three times).  Mr. Sunding needs an education and should stick to both facts and evidence.

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By w (philadelphia pa 19126)
on July 17th, 2012

the heat wave should break by october.

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By me (austin/tx/78711)
on July 17th, 2012

Climate is always more variable over short periods than long periods ... as the comparison between the 1970 to 2011 and 1912 to 2011 map indicates.

In other words, it is easy to lie with statistics to prove your point. I’m not saying that warming is not occurring ... just that it is not as dramatic as it is being presented.

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By Frank Fertitta (Beaumont, TX )
on July 18th, 2012

Charles Kaye hit the nail on the head but there are two more points to add. One, the states that showed no increase in temp or even cooler temps would indeed be affectect by the same greenhouse effect if it were really the problem. A GLARING omission in the campaign for the global warming crowd. Also, the population in the last 100 years has risen at an exponential rate and we’re looking at numbers of people in 1900 at say 400 million versus 7 billion now. That’s a lot of heat right there. Coupled with the cities’ growths like Charles said accomodate all of those people there has to be a rise in temperature! Global warming opens up a new field of job opportunities as long as the public falls for it.

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By Dave (Basking Ridge, NJ)
on July 21st, 2012

It is clear to me, and incidentally apparently also to most other people in the western world, that global climate change is happening.  Also, the atmospheric greenhouse effect is a long and well established scientific fact which even hardened deniers cannot seriously dispute. It is also known that the effects of GW are geographically uneven. For instance, the Arctic region is warming much more rapidly than anywhere else as evidenced by the melt rate of Arctic permafrost, loss of sea ice and so on. That’s all pretty much established. I have read this post, the report, the press release and looked at some of the referenced media coverage.  In this context, and in view of some of the comments here, I think it bears mentioning that the temperature data presented here is regional. Clearly the overall US temperature trend in the past 40 years is up while the century data is technically less compelling. The report discusses that.  In that respect I found it interesting and worthwhile. To the authors’ credit they do not draw sweeping conclusions in the actual report. If one erroneously attempts to interpret this particular report as presenting statistical evidence of GLOBAL warming then that would be logically incorrect because the data is REGIONAL. As Joe Marshall points out, there is far more compelling evidence for regional climate change in the US in the response of the biosphere, than these useful but necessarily limited data alone, and as presented, would suggest.  As I understand it the major ecozones in the US are progressing northwards consistently year to year and at some fairly high average rate. The effects of the trend in US regional climate change seem to be much clearer to people that take notice of nature or live closer to ‘the land’, such as many native Indians and farmers. Observations like that help put that very ‘dry’  tenths of degree type data into human perspective, as do, by the way, also some of the other posts at this site.

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By Dennis (Columbus, OH)
on August 3rd, 2012

Joe Marshall and Dave have gotten it right. Temperature data is just one facet of global warming. Unfortunately it is relatively easy to collect data and crunch numbers instead of recording nature’s responses via plant and animal behavior. Observations far outweigh raw temperature measurements in this case. I too was long a doubter of global warming, until I realized that just looking at temperature data is virtually worthless and meaningless Open your door and look outside instead. Thanks to Joe Marshall and Dave for presenting the observational evidence so clearly.

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By Patricia Watts (Occidental, CA 95465)
on August 13th, 2012

Can someone please explain to me what caused the shift in the jet stream which played a role in the Dust Bowl of the 30s? As I understand it, there was a heat wave that lasted for months, reaching temperatures sometimes above 120 degrees. Hundreds of people died from the extreme heat.

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By Dave (Basking Ridge, NJ 07920)
on August 15th, 2012

2004 NASA study:

Does this help?  From what I have read about it, the surface of the equatorial Pacific Ocean is thought to have been unusually cool and the equatorial Atlantic was also unusually warm. As a result of that particular and relatively small but important change in sea surface temperature difference, a large wind pattern referred to as the Great Plains Low Level Jet (GPLLJ), which normally crosses the gulf stream from the east, turns right and so transports the lion’s share of the moisture it picked over water up into the interior of the country, changed direction.  The GPLLJ is an LLJ. LLJ’s are types of winds that occur at much lower altitudes ( 1 or 2 km) than the north polar jet stream. (This is the one that most people have heard of and simple call the jet stream.) I don’t have any information about what anyone believes happened to that jet stream during that event.

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By Deirdre (Silver Spring, MD, 20910)
on August 16th, 2012

Cool map!  Nicely done.  It would be great to see a contoured, geographically based version (ie, without computing trends based on the political divisions, and all of North America rather than just USA) and overlaid on topography/elevation.

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By Ageoff (Faribault, Minnesota)
on October 21st, 2012

“air pollution with fine aerosols screening incoming solar radiation could also be a factor.” Scientific fact? Not! I shudder to anticipate our reaction when the heat and drought records of the dust bowl days are broken, as is the inevitable case with all records.

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By Survival Acres
on November 24th, 2012

What do the ‘Climategate’ hacked CRU emails tell us?

  In February 2010, the Pennsylvania State University released an Inquiry Report that investigated any ‘Climategate’ emails involving Dr Michael Mann, a Professor of Penn State’s Department of Meteorology. They found that “there exists no credible evidence that Dr. Mann had or has ever engaged in, or participated in, directly or indirectly, any actions with an intent to suppress or to falsify data”. On “Mike’s Nature trick”, they concluded “The so-called “trick”1 was nothing more than a statistical method used to bring two or more different kinds of data sets together in a legitimate fashion by a technique that has been reviewed by a broad array of peers in the field.”

  In March 2010, the UK government’s House of Commons Science and Technology Committee published a report finding that the criticisms of the Climate Research Unit (CRU) were misplaced and that CRU’s “Professor Jones’s actions were in line with common practice in the climate science community”.

  In April 2010, the University of East Anglia set up an international Scientific Assessment Panel, in consultation with the Royal Society and chaired by Professor Ron Oxburgh. The Report of the International Panel assessed the integrity of the research published by the CRU and found “no evidence of any deliberate scientific malpractice in any of the work of the Climatic Research Unit”.

  In June 2010, the Pennsylvania State University published their Final Investigation Report, determining “there is no substance to the allegation against Dr. Michael E. Mann”.

  In July 2010, the University of East Anglia published the Independent Climate Change Email Review report. They examined the emails to assess whether manipulation or suppression of data occurred and concluded that “The scientists’ rigor and honesty are not in doubt”.

  In July 2010, the US Environmental Protection Agency investigated the emails and “found this was simply a candid discussion of scientists working through issues that arise in compiling and presenting large complex data sets.”

  In September 2010, the UK Government responded to the House of Commons Science and Technology Committee report, chaired by Sir Muir Russell. On the issue of releasing data, they found “In the instance of the CRU, the scientists were not legally allowed to give out the data“. On the issue of attempting to corrupt the peer-review process, they found “The evidence that we have seen does not suggest that Professor Jones was trying to subvert the peer review process. Academics should not be criticised for making informal comments on academic papers“.

  In February 2011, the Department of Commerce Inspector General conducted an independent review of the emails and found “no evidence in the CRU emails that NOAA inappropriately manipulated data”.

  In August 2011, the National Science Foundation concluded“Finding no research misconduct or other matter raised by the various regulations and laws discussed above, this case is closed”.

There is simply no evidence of fraud or misrepresentation. 9 separate investigations proved this.  Yet Climategate accusations continue (to shrivel) -

Anybody that continues to claim otherwise is deliberately spreading deception.

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By Gerald Einem (Gainesville ,Fl 32605)
on November 27th, 2012

In winter areas around a forest, cleared for agriculture, are always colder at night then temperatures taken in the forest. I would conclude therefore that, as land has been cleared for agriculture,  low temperatures would drop, somewhat offsetting temperature increase due to global warming. Thus, deforestation may offset the increase in greenhouse gas pollution until our planets relentless deforestation ends Then temperatures should rise even more abruptly.

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By Andrew (Washington DC)
on March 26th, 2013

Wrong, all the evidence and AWG proponents who covered up malfeasance shows otherwise. Here’s NOAA’s own graph over 100 years. Note that while the industrial revolution was exploding and CO2 pollution was climbing rapidly as there were no pollution controls, the temperatures were in a falling trend. What you don’t see here, is the previous hundred years as temperatures fell. Explain why temperatures were falling then as CO2 levels rose from agriculture and man’s other activities burning fossil fuels? You can’t? Neither can I.

Note that for the last two decades the temperatures have been falling again as CO2 levels keep rising. Can you explain it? Neither can I.

NASA’s James Hansen had one view; 50 other NASA scientists and Hansen’s boss have another. The credentials of the 50 need to be vetted before theirs are, no? You will believe whom you want to believe - and really, that is the best argument yet to support AWG. What you believe v. what is. Science just happens not to be one of the supportable facts:

There are a number of other issues I can’‘t cover here, so I’ll let the writer below do it instead. I trust you guys and gals can explain what isn’t so and will keep trying:

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By Peter (Beaumaris Vic 3193 (Australia))
on July 9th, 2014

Really Andrew, let’s have some clear thinking.

If you take a paracetamol for a headache and the headache is not totally cured, it does not follow that the tablet had no effect. There is clearly a rhythm to global climate fluctuations, with many influences effecting it. Why must a marginal increase in co2 during a period of significant cooling totally reverse the whole effect.

Maybe a better analogy is the child on a swing. Moderate pressure on the swing as it comes back may just slow it, but the same pressure while it swings forward brings a significant new result. Today, in a period of sustained upswing, we are setting ourselves up for an upswing never before encountered in the statistically short lifespan of Homo Sapiens.

But the clearest thinkers of all will see that if you compare worst case scenarios for both camps, so-call warmists are just plain dangerous. The potential consequences of following their lead versus the lead of the deniers is different by an order of magnitude.  In one case, 100% of the population will have to adjust; in the other, perhaps just 20% of the population will survive.

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By Camburn (North Dakota)
on April 16th, 2013

A valid comparison would be the slope of rise from 1917-1945 and 1975-2000.

Otherwise you are comparing apples to pistachio nuts.

This type of article, for those with critical thinking abilities, is somewhat insulting.

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By Tom (Chapel Hill)
on July 5th, 2013

Climate Science deniers just see to create doubt, like happened with tobacco. If they create doubt, they earn their paycheck from big oil and the like. They often have software that enables them to take on the identity of several people and give the illusion there are lots of people out there that believe the poppycock they spew. Denier bots.  As Nancy Pelosi said, “who cares?!”  Pay them no mind.

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By Mauri Pelto (West Boylston)
on October 30th, 2013

This is a perfect data set for class, with 60 student I can assign them all two states to compare over the two time periods you have and contrast this with global temperatures.  The beauty no two people examine the same states. A precipitation or extreme precipitation map like this would be equally good.

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By Bruce Baker (Opelika, AL 36804)
on April 7th, 2014

Having no scientific credentials, I can only assume that both sides of this debate can support their positions, but I also believe that the data can be skewed to support any given position. Global warming (now called climatechange) is ocurring and has probably been ocurring long before man invented a thermometer.

We can all agree that our climate changes and there are ramifications to that change. However, to think that “man” can significantly stop or start an event is the heighth of hubris. This planet will defend itself with or without us.

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By David (32667)
on June 4th, 2014

I’ve examined the temperature record’s where I live in Florida for the last 33 years starting in 1980.  This is the time period where the run up in CO2 has been most pronounced.  I fully expected to find more daily records for highs than lows, you can imagine my surprise when it turned out that the number of record lows occurring for any particular day over this 33 year period was twice the number of record highs. Doing further research for the climate where I live I discovered that orange groves once grew as far north as Gainesville in north central Florida and Jacksonville on the east coast in north Florida. The freeze of 1899 change all of that and in spite of several attempts to reestablish groves there has never been an extended warm period as significant as what occurred prier to the 1899 freeze.  I was wondering if this anomaly in the “climate” ( abet for only on small location)  over the past 150 years and in particular for the last 33 years fell in the statistical probabilities of what is being reported else where around the globe

Further analysis by a friend who is an expert in statistics was inconclusive do to the complexity and amount of input data being overwhelming.  He did express the opinion that he believed the official data I presented ( from weather records that had not been “adjusted” or tampered with) made it highly unlikely that data reported elsewhere was with out an adjustment bias to make warming look more significant than it actually was.

Is there any place that has officially recorded unadjusted data that can show twice as many record highs as lows over the past 33 years? Just curious.

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By Pat Royse (42003)
on June 4th, 2014

I can definitely believe these figures, but I have only one comment. This planet was doing wonderful until man decided to punch holes in the Ozone with space exploration. Before that you could see the different seasons every year, now we are lucky to have spring for three weeks and the same with fall. If you think about it you can see the changes over the last 45 years.I feel sorry for future generations who will pay for our mistakes that we have made.

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By Tony Segro (Columbia,Pa 17512)
on September 23rd, 2014

I’m not a climatologist, nor a geologist, but I believe that while mankind contributes to climate, it’s not as large a contribution as natural phenomenon like volcanic activity. No matter what mankind does or undoes, the earth itself, along with solar and lunar activity, play a much larger role in climate. Volcanoes in the north Atlantic also contribute to glacier melting. We shouldn’t overlook nature’s contribution to climate changes.

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