Climate change is driving changes in the blooming of wildflowers at Mount Rainier National Park/Elli Theobald
Riots of blooming wildflowers are one of the joys of visiting national parks, but climate change is tinkering with the schedule of some of those flowers. At Mount Rainier National Park in Washington, for instance, all wildflower species are blooming earlier than in the past, roughly half have extended their season, and a little less than half shortened theirs, according to research conducted by University of Washington personnel.
A trio of ecologists from the university stumbled upon this alteration while collecting data on the subalpine wildflowers that bloom each summer on the slopes of Mount Rainier. As they report in a paper published online last month in the journal Ecology, an unseasonably warm, dry summer in 2015 caused reassembly among these subalpine wildflower communities.
The conditions in 2015 gave the team — consisting of doctoral student Elli Theobald, doctoral student Ian Breckheimer and biology professor Janneke Hille Ris Lambers — a preview of what subalpine communities may look like by the end of this century. By then, significant climate change is expected to permanently alter environmental cues that wildflowers rely upon and make community reassembly a more common phenomenon — with unknown consequences for species interactions in those communities.
"2015 was such an outlier that it gave us a glimpse of what this environment on Mount Rainier might be like toward the end of this century," said Theobald, who is co-lead-author on the paper with Breckheimer. "Conditions were so warm that they affected the flowering time and flowering duration of species, forming communities in 2015 that simply did not exist in the other years of our study."
Their study is one of few to demonstrate evidence for community-level reassembly among multiple species.
"These reassembled communities could potentially change the interactions among wildflowers and other species in this subalpine setting," said Theobald.
For six summers from 2010 to 2015, Theobald tracked environmental conditions and plant behavior for 48 species at 70 field plots, each one square meter, along the southern slope of Mount Rainier. The plots ranged from 1,490 to 1,901 meters in elevation. Within each plot, Theobald used sensors to record temperature, snowmelt, and soil moisture content.
"At these elevations on Mount Rainier, snow is the major driver of plant behavior, because the annual cycle of flowering and reproducing cannot begin until the snow melts," said Hille Ris Lambers. "If there is snow on the ground, plants cannot photosynthesize, and if they cannot photosynthesize, they cannot grow."
All wildflower species at the park are blooming earlier, and a little more than half are staying in bloom longer/Gary Vogt file
When the sensors reported that snow had melted at each plot, Theobald collected data on when plants would emerge, flower, and begin to produce fruit. These included species familiar to hikers such as avalanche lily, magenta paintbrush, mountain blueberry, wild huckleberry and wild lupines.
Most of these plants are perennials, which retreat underground each winter. But when snow melts, they typically have a two- to four-month window — depending on elevation and position — to grow, flower and produce fruit and seeds for the next generation before snow returns.
In 2015, conditions were so warm that, on average, snow began to melt at the study plots 58 days earlier than in 2010-2014. The team recorded major shifts in the bloom times of wildflower species. All of the species — 100 percent — flowered earlier in 2015 and 54 percent of species also lengthened their flower duration that year, some by as many as 15 days. The remaining species showed shorter flower duration, in one case by nearly 19 days, possibly due to accelerated soil drying, altered pollinator activity or other factors.
Since species shifted in different ways, conditions in 2015 produced new patterns of reassembled wildflower communities, with unknown ecological consequences.
"These are species that have always coexisted at these subalpine sites," said Theobald. "But in 2015, we saw species flowering at the same time that normally flowered weeks apart."
The team saw the most dramatic signs of reassembly among plants that normally flowered early in the summer. These plants tended to grow at sites experiencing less snowfall — such as plots at lower elevations, or along ridges and slopes instead of coves and valleys, where snow tends to accumulate. In addition, the plants that tended to lengthen flowering duration did so if they experienced a greater number of warm, photosynthetically "productive" days in 2015.
Reassembly on the scale that the researchers saw in 2015 — and that Mount Rainier may see every year by the end of this century — may change interactions among species. For example, plants could compete for access to pollinators, which at Mount Rainier include bumblebees, flies and hummingbirds.
"We simply don't yet have enough information to know who the 'winners' and 'losers' of reassembly will be, or even what 'winning' or 'losing' in such a scenario would look like," said Theobald.
To predict that, scientists must observe and test how ecological reassembly affects reproduction for all species in these regions — from flowers and pollinators, to even the bears that feed on subalpine berries. These effects will also impact the people who visit these sites and try to preserve them.
"All of these interactions among species — and how those interactions will shift due to climate change — will affect how we manage these sites," said Hille Ris Lambers. "After all, Mount Rainier is a national park that is here for all of us, as well as the species that call it home."
Glacier lilies in bloom at Mount Rainier/Rebecca Latson file
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Comments
Yes Rick, you got played the fool again so you will run and hide. The study is the study, its conclusions have nothing to do with who reports them.
I don't know. You could listen to scientists about science or some guy who sells houses about science.
And now a word from the other side. Drum roll, please!
https://www.amazon.com/Water-Will-Come-Remaking-Civilized/dp/031626024X/...
Has anyone been to the city shown in the illustration? If not, what is the illustration meant to "convey?" A "promised" reality? The Water Will Come? I have news for the author and publisher. The "water" is already here. If I build next to the ocean, just what can I expect? Stability? Sea levels NEVER rise? Tell that to the Bering Land Bridge.
But this illustration? Now you see why the skeptics are skeptical. If all you can do is scare me, your argument had better point to a fright that is real.
Toxie, perhaps you missed it. The link wasn't to a study I conducted, it was to a study that scientists conducted and was published in a peer reveiwed journal that focuses on atmospheric sciences.
I am somewhat bemused by the majority of comments posted about this article. The original article was mostly about ecological changes in the context of global climate change. Yet, almost no one focused his/her comments on what the article had to say or what, if anything, should be done about trying to protect parks from global climate change. Rather, some comments referred to Al Gore, as if is the all-knowing climate change guru. He is not. And scientists writing about the science of global climate change do not reference him in their studies, at least for the most part. In addition, people ask whether and why we should look to see past geological/climate epochs as the most "ideal" to live in.
Over the past 250-300 years the earth's mean atmospheric temperature as risen about 1.1 degrees C due to human activities, mostly fossil fuels. The types of changes discussed in the article have occurred in response to the rise in temperature since about 1750 or so-again, mostly from fossil fuels.
When climatologists use the term "Eemian" as a preferable baseline for atmospheric temperature, they do so because it was a relatively warm period and one that was very favorable to the evolution of humans and other organisms. If atmospheric temperatures are kept within Eemian bounds, we would spare ourselves from the more drastic impacts of, say, a 2 degree C change.
Climate change is not a trivial issue. It involves real harms to real people-most who live in conditions of poverty and who have contributed least to the problem. Dismissing the uncertainties as Dr. Runte does does nothing to promote mitigation of climate change and hence help protect places like Mt. Rainer.
And there is absolutely no evidence to support that claim.
1) I agree with John Lemons comment: the post is about empirically observed shifts in phenology. What's important and an advancement in our knowledge in that research is not that wildflowers are blooming earlier (which can mess up the timing of pollinators, but is well-established), but that different sets of wildflower species are responding differently. Some have flowering time diven by days since snowmelt, others by degree-days or soil drying out because they do more photosynthesis & growsth before flowering, so the sets of species flowering at the same time are being scrambled. That scrambles which species are competing for generalist pollinators, and which are the simultaneous options for generalist herbivores. I interacted with Janneke when she was a grad student at Duke. Both she and her advisor were wicked-smart, careful, and rigorous;. I expect she teaches her students to be the same. [There are several Dookies I would _not_ make that statement about.]
2) ec: Your links were actually to two different news or opinion pieces about the study. Here's the actual paper on temperature trends estimated from satellite data for you to read (linked from a source you would approve of, because the Journal site wants $40 for the pdf): https://wattsupwiththat.files.wordpress.com/2017/11/2017_christy_mcnider...
I've only skimmed the paper, as it isn't my field. Note that it is published in a low impact journal (Asia-Pacific Journal of Atmospheric Science) published by the Korean Meteorological Society, a bit odd for U Alabama Huntsville authors, and not a journal that has published global-scale instrumentation vs model sensitivity papers in the past, nor was this a topical special issue. Perhaps there's a positive reason for publishing this work in that journal; perhaps the authors felt peer reviewers in higher profile more relevant international or American journals would be unfair to their work. The journal choice doesn't mean the work is wrong; it does indicate the manuscript went through much less rigorous peer review (if any: not even anonymous reviewers are acknowledged, and this isn't a topic the editors have expertise in, and without prior similar papers in this journal, their list of potential reviewers (mostly authors who previously published in their journal) might not include any with specific expertise, either). Over the next month or so, other researchers will examine this work, and peer reviewed responses & extensions will start appearing in a year or so.
If you read the paper, you'll see that Christy & McNider apply new corrections for the effects of volcanic eruptions and ENSO cycles to the 38.5 years of record for satellite-based measures of lower troposphere air temperatures. Their result is that their new estimates are that one component of the earth (lower troposphere) is only warming ~1deg C per century instead of 1.5deg C per century (their uncertainty about those estimates isn't clear; I don't believe 3 decimal places .096/decade vs .155/decade). They then use those new values to claim that the sensitivity to CO2 is overestimated in most climate change projection models. Most models of heat fluxes have much more heat going into shallow ocean temperatures (deep ocean responses are a great unknown) and higher latitudes and even mid-troposphere, and different approaches to measurements of those components show larger trends than 1deg C per century, so I honestly don't know what to make of these results for the lower troposphere, assuming they are solid. That's certainly not "...casts doubt on media's climate change fairy tale" or "no _acceleration_ (sic) in global warming in 23 (sic) years"; the headlines of your links. I haven't a clue what models you think it proves wrong; I (uncharitably) suspect you don't know, either.
[Some of their approach, such as 9 predictor variables with lags from 0 to 12 months for each, then treating different overlapping subsets of the years of record as separate "experiments", raise red flags for me, especially when they give no citations for their statistical methods, but this isn't my field, maybe they were using something akin to Theil-Sen to estimate slopes but didn't know the name, so I await more informed reviews & responses.]
If you want an idea of some of the other issus with these satellite data, look at
http://journals.ametsoc.org/doi/pdf/10.1175/JCLI-D-13-00767.1 (cross comparisons of mid-troposphere temperature estimates)
http://journals.ametsoc.org/doi/full/10.1175/JCLI-D-16-0768.1 (adjusting for diurnal shifts in satellite overpass times)
There's also something new in Nature, but it isn't open access, and I distrust papers in Nature & Science because of the abbreviated Methods sections (I wait for the more detailed papers in solid but not as flashy journals so I can understand what was done, not just the results).
I deal with the instrumentation record for temperatures & precipitation for North America for the past century. There's missing data when instruments break, there's drift between calibrations, and occasional outlier values, especially for precipitation. Climatologists are pretty rigorous about how they fill in missing values from relationships with nearby sites, and then (conservatively) use those estimated values if simply omitting those days would bias the results (e.g., missing all of January would make that year's average temperature appear higher than normal). For outliers, if several nearby stations have outlier precipitation at similar dates & times, there probably was a real weather event driving those outlier values. If not, there's a question of where to make the cutoff for deleting as instrumentation error versus retaining as rare event. It turns out that different NOAA regional climate centers use different thresholds: the midwest filters out a few more more extreme values because they're informing crop models; the western regional climate center has a higher cutoff because microbursts & extreme thunderstorms are important processes for rangeland and hydrology. What each center does is appropriate for their intended uses; my mileage might vary for my different uses of the data. [Gridded climate data like PRISM or DayMet have a whole additional set of issues to be aware of before using them.]
I'm an ecologist, using climate data as covariates for the biotic trends I'm interested in (are bird & plant populations really trending, or were that year's values low because of a drought?). But to do my science right, I have to know at least as much as the above paragraph about what the climate data are, so I don't do stupid things like treat those differences in the processing of instrumentation as differences in the climate that might drive differences in the plants. I also have to be careful to track the uncertainty of my estimates. I have to be careful so I don't mislead myself, and mislead park resource managers. I acknowledge that not _all_ scientists are so rigorous about their work, but most are. By comparison, the writers in Daily Caller and Investors Business Daily don't appear to need or have that level of understanding of the paper they wrote about. Almost as if the results of the Christy & McNider paper didn't matter for the narratives in their articles.