From the University of Arizona
Warming climate pushes plants up the mountain
Comparing plant communities today with a survey taken 50 years ago, University of Arizona-led research provides the first on-the-ground evidence for Southwestern plants being pushed to higher elevations by an increasingly warmer and drier climate
In a rare opportunity to directly compare plant communities in the same area now with a survey taken 50 years ago, a University of Arizona-led research team has provided the first on-the-ground evidence that Southwestern plants are being pushed to higher elevations by an increasingly warmer and drier climate.
The findings confirm that previous hypotheses are correct in their prediction that mountain communities in the Southwest will be strongly impacted by an increasingly warmer and drier climate, and that the area is already experiencing rapid vegetation change.
In a rare opportunity to obtian [sic] a “before – after” look, researchers studied current plant communities along the same transect already surveyed in 1963: the Catalina Highway, a road that winds all the way from low-lying desert to the top of Mount Lemmon, the tallest peak in the Santa Catalina Mountains northeast of Tucson.
“Our study provides the first on-the-ground proof of plants being forced significantly upslope due to climate warming in southern Arizona,” said Richard C. Brusca, a research scientist in the UA’s department of ecology and evolutionary biology who led the study together with Wendy Moore, an assistant professor in the UA’s department of entomology. “If climate continues to warm, as the climate models predict, the subalpine mixed conifer forests on the tops of the mountains – and the animals dependent upon them – could be pushed right off the top and disappear.”
 |
||||
 |
 |
|
 |
|
|
 |
  IMAGE: Today, living alligator juniper first begin to make an appearance on upland slopes of the Catalina Mountains at around 5,000 feet elevation…
|
|
|
|
 |
|
 |
|
|
||||
The study, published in the journal Ecology and Evolution, was made possible by the existence of a dataset compiled 50 years ago by Robert H. Whittaker, often referred to as the “father of modern plant ecology,” and his colleague, William Niering, who catalogued the plants they encountered along the Catalina Highway.
Focusing on the 27 most abundantly catalogued plant species, Brusca and Moore discovered that three quarters of them have shifted their range significantly upslope, in some cases as much as a thousand feet, or now grow in a narrower elevation range compared to where Whittaker and Niering found them in 1963.
Specifically, Moore and her team found that the lowermost boundaries for 15 of the species studied have moved upslope; eight of those species now first appear more than 800 feet higher than where Whittaker and Niering first encountered them. Sixteen of the studied species are now restricted to a narrower band of elevation, the researchers noticed. As far as the plants’ upper elevation limits were concerned, the researchers observed a mixed trend: They found it to be higher for four species, lower for eight species and unchanged for 15.
For example, in 1963 Whittaker and Niering recorded alligator juniper as a component of upland desert and grassland communities in the Catalina Mountains, beginning at an elevation of just 3,500 feet. Today, one has to drive to the 5,000-foot elevation marker on the Catalina Highway to see the first live alligator juniper trees in upland habitats.
According to the authors, the main point emerging from the study is that plant communities on the mountain were different 50 years ago because plant species do not necessarily move toward higher elevations as a community. Rather, individual species shift their ranges independently, leading to a reshuffling of plant communities.
The scientists in this multidisciplinary group gathered the data during fieldwork in 2011, and included UA postdoctoral fellows and professors from several programs, including the UA departments of entomology and ecology and evolutionary biology, the Center for Insect Science and the Institute for the Environment, as well as botanists from the Arizona-Sonora Desert Museum.
|
||||
|
|
|
|
|
|
|
 IMAGE: …However, below 5,000 feet, hundreds of dead juniper attest to a former range much lower down on the mountain, reflecting cooler and wetter years of the past.
|
|
|
|
|
|
|
|
|
||||
Based on studies done by other scientists, including UA researchers, the researchers believe that a “thirstier” atmosphere might be a major driver behind the shifts in plant distribution, possibly even more so than lack of precipitation. As the atmosphere becomes warmer and drier, plants loose more water through their leave openings and become water-stressed.
According to the authors, the results are consistent with a trend scientists have established for the end of the Pleistocene, a period of repeated glaciations that ended about 12,000 years ago. By studying the distribution of plant seeds and parts preserved in ancient packrat middens, for example, paleo-ecologists have documented that as the climate warmed up, plant communities changed profoundly.
“In southern Arizona, some species moved north to the Colorado Plateau, others moved up mountain slopes, and others didn’t move at all,” said Moore, who has been collecting data on ground-dwelling arthropods, plants, leaf litter, weather, soil, and other ecological factors in the Santa Catalina Mountains for the Arizona Sky Island Arthropod Project based in her lab.
The Sky Islands encompass an “archipelago” of 65 isolated mountain ranges rising from the surrounding low-elevation desert and desert grassland in an area that constitutes the only major gap in the 4,500-mile long North American Cordillera, which runs from northern Alaska to southern Mexico. The Sky Islands, often referred to as the “Madrean Sky Islands,” span this gap in southeastern Arizona, southwestern New Mexico and northeastern Sonora, Mexico. They include the Santa Catalina Mountains, the Pinal Mountains and the Chiricahua Mountains.
Research publication: http://onlinelibrary.wiley.com/doi/10.1002/ece3.720/abstract
“As far as the plants’ upper elevation limits were concerned, the researchers observed a mixed trend: They found it to be higher for four species, lower for eight species and unchanged for 15.”
1) So were talking only 4 of the plant species walked up higher than their previous range out of 26. Why would 8 walk down from their higher range into worsening conditions. With such an imprecise type of population isn’t this within standard deviation? Maybe the earlier survey was 20 feet farther over?
2) a rise of 100m is equivalent to a drop in 0.64C on average (temp rise was smaller than that since 1963).
3) Moving upward in latitude 100 km would drop the temp about the same (likewise undoing the climate change.
4) A better survey: examine north and south facing slopes for corroboration of the affect of metrics. Check out other hills in the vicinity to get standard deviation data. Do the survey 90 to 100 km north of this site. Evaluate what has changed since 1963 – paving the road? a grass fire in 1975? 10 fold increase in traffic? Deer like the plants that went up the hill so dramatically?
No, if they hadn’t found some change they could worry everybody about, they would have done these other things. Maybe we should fund a Steve McIntyre expedition to check the data.
Is a Bristlecone a treemometer or is it a treehygrometer? Similarly, is a given succession a manifestation of temperature change or a shift in orographic yield (e.g. due to more or less incident moisture). Here is a paradox. The hotter the Western Desert, the more the uplift and the more the Monsoon gets pulled in. Same applies in Asia. Conversely the colder the desert, the the drier and the “orographic” islands retreat further uphill.
@ur momisugly Pamela Gray August 15, 2013 at 9:50 am –
LOLOL!
I love this: “Our study provides the first on-the-ground proof of plants being forced significantly upslope due to climate warming in southern Arizona,”
The poor plants do not just migrate voluntarily upslope, no, they are “forced”.
The Sonoran Death March is upon them
In California’s Sierra Nevada mountains during the MWP (roughly 1000-1200CE), tree lines were 300-500 meters (~1000-1500 ft) higher than at present. This implies summer temperatures over 3C higher than at present. And the instrumental record shows no trend at all in Sierra temperatures for the 20th century.
@Pamela Gray:
“Jim you have got to be kidding! What half-brain thinks that dredging harbors would lower ocean sea levels????”
Jims says: Quite frankly, I haven’t found them yet. But, today I came across a half wit who thinks that trees are going to be pushed off the top of mountains and disappear due to climate change. So I am sure I will come across them soon enough when a read a few more CAGW articles.
Jim Hansen said that our oceans are going to boil away from the effects of climate change, and he was a NASA scientist at the time when he said this. So anything is possible, since it is quite apparent that one can be a scientist and be a half wit at the same time.
Chris Schoneveld says:
August 15, 2013 at 12:35 pm
I love this: “Our study provides the first on-the-ground proof of plants being forced significantly upslope due to climate warming in southern Arizona,”
The poor plants do not just migrate voluntarily upslope, no, they are “forced”.
Chris,
Moore’s et.al. repeated use of emotive lexicology struck me as well! Following their ’emotional logic’, I suggest we just march up to 5000 feet and tell those damn triffid-like junipers to get the hell back down the slope or we’ll turn their sorry root stocks into firewood and charcoal! That should get them jumpin’ junipers moving back down slope in short order…… because we sure wouldn’t want them to get “pushed right off the top and disappear.”
MtK
Is there anyone who has denied that the climate has warmed by about 0.6C over the last century?
Latitude says:
August 15, 2013 at 9:12 am
However, below 5,000 feet, hundreds of dead juniper attest to a former range much lower down on the mountain, reflecting cooler and wetter years of the past.
====
uh guys, that’s a picture of a tree that died of Juniper blight….a fungal disease
Oh, Latitude, a stupid thought came to my mind reading this: was there not a case where species of frogs where thought to die due to global warming?
Something like this:
http://www.sciencedaily.com/releases/2008/10/081028184830.htm
And in the end it was found out that the researchers were spreading a fungus and contaminating frogs all over?
Could it be that somehow fungal diseases were spread in the region?
As CO2 enrichment makes plants more resistant to droughts I have a bit of a problem digesting the narative. There is no data showing how much the temperature changed, how drier it became?
“Moving upward in latitude 100 km would drop the temp about the same …. .” [Pearse at 11:34AM]
Ah, good point, but, then the trees could not be “forced” off the top! lol
They THOUGHT of doing a little “research” along the southern side of the Grand Canyon, but people know too much about those sturdy little burros and would never believe a TREE could fall off, but, on the top of a mountain, IT JUST MIGHT HAPPEN. {O.O}
***
Caleb says:
August 15, 2013 at 10:56 am
The range of sugar maples retreated to the north in the MWP, and though Puritans transplanted it south when they arrived in the Little Ice Age the Indians in southern New England sneered at “sugar-eaters,” while those to the north relished maple sugar.
***
Where I’m at in west MD, sugar maples are invading southeastward into the existing oak/hickory forests, locally here at lower elevations & encroaching into the adjacent uphill areas.
Lars P: As CO2 enrichment makes plants more resistant to droughts I have a bit of a problem digesting the narative. There is no data showing how much the temperature changed, how drier it became?
=======
Unfortunately there is….they start out assuming temps have increased in Arizona…then go looking for an effect
You can’t get temp increase in Arizona without changing the temp history…and creating a whole new temp record…drought graphs for Arizona are flat…no change
http://stevengoddard.wordpress.com/2013/04/07/raising-arizona-3/
Can I die from “rapid vegetation change?”
Post hoc ergo propter hoc.
Fail.
I recall a similar study about Alpine plants; can’t remember the details.
jbird says:
August 15, 2013 at 10:55 am
The whole AGW hoax has been successful in part because too many of us now live our lives indoors in hermetically sealed urban environments. We simply don’t get enough opportunity to observe the natural world for ourselves and to develop a common sense view.
________________________________
Recently i have started to suspect that this very situation, the predominance of western and increasingly ROW citizens living in what are almost completely isolated from the real out there Nature in near hermetically sealed, deep urban environments is rapidly leading a very substantial corruption of environmental research by the long time urban dwelling, university educated researchers,
With no experience worth counting of real time Nature during their previous life, they now harbor personal views of the natural world and the way in which the incredible array of all the elements that make up that ever changing, ever interacting and evolving and adapting natural environment as a sanitised chimera of Nature that only exists in their imagination.
And thats how they start their time as researchers and political policy wonks when they reach the stage of being included in the decision making circles.
There is now a huge disconnect becoming apparent in research and policy making highlighted by the real time experiences of the often quite rapid Natural changes to local environments as seen and experienced by so many posters above [ as is also the case with this rural dwelling retired farmer,] between what happens in real time Nature and the real world compared to the glorified and highly sanitized view of Nature by seen by urban dwellers and even more so by the highly paid inner city elite who today are the most likely to take up some sort of environmental studies or get involved in policy making.
Some of them cannot and / or will not ever abandon this corrupted, sanitised urbanised chimera of Nature and their research and any policies arising from that research will consequently be not only seriously bad but both highly misleading and consequently worthless and even quite harmful to both Nature and to the rural dwellers, rural industries and workers.
The fact that over half the world’s population now live in cities of over a hundred thousand or more in population spells some quite serious problems ahead for the rural industries and dwellers and for research and policy making in so many fields where the environment is involved even if only peripherally.
The corrupted view of what is supposedly natural and the way in which the ever proliferating restrictions on food production and energy and mining technologies by the urbanised elite and their sanitised view of the world outside of their own tiny completely artificial environment will quite conceivably have drastic consequences for global food, energy and commodity production and for those still living in a non urban, rural environment in the decades ahead..
Warming climate pushes plants up the mountain… Alternate headline..”No longer CO2 starved, plants able to survive at higher elevations.” It takes quite a bit of work to make that into something negative.
INCREASED CO2 EXTENDS PLANT RANGES
Aren’t we forgetting that increased carbon dioxide in the atmosphere enables plants to extend their ranges into areas that were once unsuitable? How much of this expansion into higher altitudes is simply due to higher levels of CO2 — not global warming?
This seems something of utmost importance — that the author’s have missed.
Increasing an important fundamental plant nutrient would have a far greater effect than a small increase in atmospheric temperature.
Actually this is testable. Two green houses set side by side. Set the conditions of the green houses at a level where the chosen plant is barely surviving. Increase CO2 in one and temperature in the other. Under which circumstance will the plant best flourish?
Eugene WR Gallun
Latitude 9:12 am says
Uh guys, that’s a picture of a tree that died of Juniper Blight … a fungal disease
Tears in my eyes from laughing!
Eugene WR Gallun
Eugene WR Gallun
JUNIPER BLIGHT MOST DEVASTATING DURING WET CONDITIONS.
Authors state that Junipers thrived during an earlier wetter period. Just learned Juniper Blight is most devastating during wet conditions. So the conditions that the authors claim lead Junipers to thrive were quite possibly the conditions that actually brought about their demise.
Eugene WR Gallun
Thanks, Tim Ball @ur momisugly
August 15, 2013 at 10:39 am
I agree that this line of research is important to climatology. People in their haste to denigrate “treemometers” should think about what trees have to show us. In Colorado backpacks, I’ve seen the dead, white trunks of enormous bristlecone giants strewn about the scree slopes and boulder fields several hundred feet above the timberline of present-day bristlecone pine. This is a tree that is so slow-growing and dense (its rings can be fractions of a millimeter apart) that it takes a dead tree hundreds of years to decay at altitudes of 13,000 feet. With nothing but rocks in between these behemoths and existing treeline, I can only conclude that several hundred years ago, clement weather gave them an advantage, and they took the opportunity, as all species will, to move into a new niche. These are relict species of the Medieval (or perhaps some more recent) Warm Period.
Obviously this kind of species movement and adaptation is anything but new, as warm and cold periods come and go across the globe..
HH Lamb noted in his book “Climate History and The Modern World” that
I’m glad to see that trees are now figuring out they should migrate upward. It was pretty bad watching them all moving north. At first the US side of the border were trying to keep them from leaving for Canada, then the Canadian side was trying to keep them out since we’re full. But they just crossed anyway.
I mean really, after watching a few million trees moving north across the prairies you just tire of the whole thing. I can’t even describe some of the highway traffic jams at the tree-crossing points, especially on the east-west highways. Sometimes it would take hours for a forest to pass by, there were so many trees. There were so many you could hardly even see the forest!
Now, as we all know, the ones that were forced to move north are pretty much stacked up at the edges of the Arctic Ocean, staring out at the lukewarm ice-free water. They seem to yearn to go farther north, but there is no way. The surviving polar bears won’t let them.
I weep for our planet…
It would perhaps help the researchers to know that we just emerged from 50 years of warming, with some overlap, and we have already entered 50 years of cooling.
http://blogs.24.com/henryp/2012/10/02/best-sine-wave-fit-for-the-drop-in-global-maximum-temperatures/
http://blogs.24.com/henryp/2013/04/29/the-climate-is-changing/
Catalina Highway construction began in 1933 and was completed in 1950. In 1963, Whittaker and Niering did their study. Then this bunch do their study 50 years later and attribute the migration of plants to “climate change”. I have a lot of problems with this study, first and foremost is they don’t know the distribution of the plants in 1913, 1863, 1813 and so on back. Then my question is, can any of this migration be attributed to the construction of the highway itself? Whenever man alters the landscape, the flora and fauna change also. I see numerous examples of highways, logging roads and fire trails altering the distribution of the flora and fauna along their routes – up hill and down hill.