More Evidence, As If We Needed It, of Global Warming, part four

I conducted a sixteen-year study of budburst dates in Oklahoma deciduous trees, and I found that winter buds opened in spring earlier and earlier each year, consistent with global warming. The results were highly significant. I did not, however, have time to publish this study in a scientific journal before I retired. I decided instead to publish it on my website. Here is the link to the article, with illustrations. Please note that the mailing address on the cover page is now obsolete; you may contact me through the website email link (stanriceauthor@gmail.com).

I here address an interesting point about this research, aside from its unsurprising conclusion. And that point is, what do we do with the data?

(This is a photo of the just-opening buds of black hickory. Oaks have lots of bud scales, but hickory just has two big scales for each bud.) 

My statistical analyses indicated quite clearly that all but one of the 22 tree species had earlier budburst over the course of 16 years—an average of about one day earlier each year. But this is an average. Budburst came later in silver maples—but this is because they died in the summer droughts. Pecan trees opened their buds about one day earlier each ten years, whereas sweetgums opened their buds about three and a half days earlier each year. This means the makeup of our forests might change with global warming, since not all tree species will react to it the same way.

Also, it is completely incorrect to assume that global warming means that each year is warmer than the previous year. One year can differ strikingly from the next. What we are looking for is an overall trend. This is obvious from the data presented in my graphs in the paper.

Science must also avoid what is called extrapolation. We cannot simply take this one-day-per-year rate and extend it into the past or the future. Particularly, the future. If, for example, sweetgums opened their buds three and a half days earlier each year (with the average date in my study being February 24 in 2009), this would mean that in 2029 they would open in the middle of winter, about December 19, and back in 1999 they would have opened at the end of March. I was on site in 1999, though I’d not yet begun my measurements. But I know they opened before the end of March. And they cannot open their buds in December unless winter completely vanishes. This is unlikely to happen. At least, not soon.

What this means is that one-day-per-year earlier budburst is what I observed in the study period, but there were earlier times, and may be later times, when this rate did not occur. Extrapolation is invalid, as Mark Twain explained. If the Mississippi River gets 10 miles shorter each year, then at some point, Twain quipped, St. Louis and New Orleans would be next to each other and need a joint board of aldermen. If it gets 10 miles longer each year, then in a few years it would stick out over the Gulf of Mexico (Gulf of America?) like a fishing rod.

Scientists should not extrapolate beyond their data. We can interpolate, within the range of data, but not extrapolate outside of it. All I can say is, this is what happened during my sixteen-year study period. As you can see from the figures in the paper, budburst dates sometimes came earlier (especially 2017) and sometimes later (for example, 2018). It changes every year, but these changes are against a background of earlier budburst, as indicated by the statistical analyses.

Yes, sixteen years in which at least twice a week, during February and March, I walked past each tree and looked for budburst. It sounds like a lot of boring work. But it was not, for me: I came to know each of these trees as an individual, and I looked forward every year to its emergence from dormancy.

As indicated in these four essays, the science of global warming is not just something to argue about—and we are all tired of arguing—but an invitation to the adventure of scientific discovery. We can, by using science, listen to what the trees have been telling us all along.

More Evidence, As If We Needed It, of Global Warming, part three

I am posting this on the day on which Europe is having its warmest May on record, passing previous records by a long ways. The ways I am keeping cool is by sitting under ceiling fans and not doing much except writing. But this series of essays is not about global temperatures directly, but about their effects on the seasonal activities of plants.

I conducted a sixteen-year study of budburst dates in Oklahoma deciduous trees, and I found that winter buds opened in spring earlier and earlier each year, consistent with global warming. The results were highly significant. I did not, however, have time to publish this study in a scientific journal before I retired. I decided instead to publish it on my website. Here is the link to the article, with illustrations. Please note that the mailing address on the cover page is now obsolete; you may contact me through the website email link (stanriceauthor@gmail.com).

I here address an interesting point about this research, aside from its unsurprising conclusion. And that point is, how do we avoid bias?

Here is a photo of mulberry buds.

Everyone is biased, including scientists. The people who proclaim themselves to be unbiased (politicians, industry leaders) are in fact the most biased people in the world. Scientists are much less biased, and for good reason. The process of scientific research requires specific steps to be taken to deliberately avoid bias. So, when I conclude that global warming is occurring, a politician (such as the infamous Oklahoma Senator Jim Inhofe, who said whatever oil companies paid him to say) could accuse me of being biased. This is true, but I, unlike him, deliberately designed my research to minimize the bias. Take that, Jim Inhofe! I cannot tell him this, because he died in 2024.

Here is how I did it. For sixteen years, I walked around and noted the budburst dates of a couple of hundred trees. In the back of my mind, I was thinking that the sixteenth year would have much earlier budburst dates than the first year. That, of course, is bias. But budburst is a continuous process. If you note down the very earliest date on which the buds appear to reawaken in the spring, you get an early budburst date; if you note down the first date that the leaves or flowers emerge from the bud, you get a medium budburst date; if you note down the date on which the leaves or flowers are fully expanded, you get a late budburst date. I had to choose some indicator of budburst; I chose the date on which the bud swelled just enough to allow the tissues inside the bud to be visible. And once I had chosen this indicator, I had to stick with it for sixteen years. You can see this in the color photos I included in the article, and in these blog essays.

The technical term for choosing a standard of measurement is construct validity. You can read about it in my book about the adventure of scientific discovery.

There is, in addition, a tradeoff between how detailed your observation can be and how many observations you can make. You cannot measure everything everywhere. When it comes to spring budburst studies, they fall into two categories:

First, satellite measurements. Satellites can measure buds turning green in the spring over hundreds of square miles. This allows the results, such as earlier budburst, in any one location to be generalizable over a larger area. This gives satellite measurements external validity, that is, they are valid not just for the area in which the measurements were made.

Second, there are ground-based studies, such as mine. I am sure of the budburst date and species for each tree. But, as I openly admit in my article, the external validity of ground based studies is limited.

I will explain, in the next essay, yet one more interesting point about scientific research into global warming.

More Evidence, As If We Needed It, of Global Warming, part two

As described in the previous essay, I conducted a sixteen-year study of budburst dates in Oklahoma deciduous trees, and I found that winter buds opened in spring earlier and earlier each year, consistent with global warming. The results were highly significant. I did not, however, have time to publish this study in a scientific journal before I retired. I decided instead to publish it on my website. Here is the link to the article, with illustrations. Please note that the mailing address on the cover page is now obsolete; you may contact me through the website email link (stanriceauthor@gmail.com).

I here address an interesting point about this research, aside from its unsurprising conclusion. And that point is, what do we measure?

This photo shows the giant buds, just opening, of black oak (Quercus velutina).

When we talk about global warming, we can mean lots of different things. It is better to talk about global climate change or even global climate disruption. For global warming, it would seem to be a simple matter of measuring temperatures and seeing if they increase from year to year. But this, by itself, is unsatisfactory, for reasons such as these:

Where do you measure the temperature? Air temperature may be warmest near the ground, and cooler the further you go up in the atmosphere. Air temperature is what affects budburst, since buds are up in the air. But soil temperature is also important, since warmer soil might mean earlier root activity and earlier rising of the sap. Aerial buds do not just open when it is warm enough but also in response to sap rising in the wood.

Temperature is enormously variable. You cannot simply measure it in one place and use this temperature to represent the air temperature. Meteorologists have little stations to measure air temperature (and lots of other things) in numerous locations, but even this is not enough. Temperatures can vary from one location to another just a few feet away.

When do you measure the temperature? The maximum temperature in the day, or the minimum at night? Also, we suspect that springtime temperatures are what matter the most, but winter temperatures can also be important. Some tree buds must have a certain number of days of winter chilling before they can open in the spring.

Other factors are always important, such as wind speed, soil moisture, and the moisture status inside the twigs.

It is not just the temperature that matters to humans, but how it makes us feel. Weather predictions indicate not only the actual temperature but the way it feels to the body. The same is true of trees. We are interested not so much in the actual temperature of the air as in how the temperature affects biological activities such as the opening of the buds.

The climate could be getting warmer even if the temperatures do not increase. Springtime could just come earlier and autumn later, without a change in the average temperature.

If all of this makes it seem hopeless to study global warming, I am happy to report that organisms themselves can transduce all the environmental variables, over time, into biologically meaningful measurements. In the case of trees, all of the variations in temperature, moisture, and wind can be summarized by budburst date, something that the plants, not we, control. Budburst date is the one variable I measured. I used weather data as background, but not for analysis.

By opening their buds earlier and earlier each year, the trees are telling us that it is getting warmer. See the next essay for other scientifically important concepts in the study of global warming.

 

More Evidence, As If We Needed It, of Global Warming, part one

I conducted a sixteen-year study of budburst dates in Oklahoma deciduous trees, and I found that winter buds opened in spring earlier and earlier each year, consistent with global warming. The results were highly significant. I did not, however, have time to publish this study in a scientific journal before I retired. I decided instead to publish it on my website. Here is the link to the article, with illustrations. Please note that the mailing address on the cover page is now obsolete; you may contact me through the website email link (stanriceauthor@gmail.com).

Here is what I indicated on my website:

Global warming is something that is already changing the world in a way that will make human civilization difficult. One indicator of global warming is that buds open sooner in the spring than they did previously. Here you will see the evidence.

It is difficult to think of a more important scientific topic today than global warming. The Earth is getting warmer far more than it ever did in the past by natural climatic variation, and the reason is clear: humans are putting massive amounts of carbon dioxide into the atmosphere. There are many consequences of this, for the natural world and the human world (for example, food production). The subject could fill an encyclopedia; as a matter of fact, I was under contract to write the Encyclopedia of Global Warming for Facts on File, but they discontinued the project before I had written any actual entries, just the overview.

Every scientist and scholar, except for fringe people who are either dedicated to extremist politics or paid by corporations, accept the reality of global warming and its human cause. Even many Republicans accept it, although most of them have now been kicked out of the Party. Even Exxon-Mobil accepted it decades ago, until they repudiated their own research for political reasons. The United States is the only major country in the world in which the government opposes the science of global warming. First George W. Bush, then Donald Trump, removed global warming from government websites. Other countries, such as in Europe, know that they can no longer trust American scientific information about global warming.

One reason for this worldwide acceptance of the science of global warming is that it is confirmed by the convergence of many different lines of research. Fields as different as meteorology, geology, and biology all confirm that global warming is real. One small area of research is one in which I was involved: phenology, which is the seasonal patterns of biological activity. In particular, deciduous trees lose their leaves every autumn and open new buds in the springtime. In recent decades, with global warming, tree buds have been opening earlier and earlier in the spring.

Many different sets of data confirm this. Many of them result from satellite measurements which show that forests turn green earlier every spring. Some are based on direct observations of trees and other plants. I have a data set that I worked on for sixteen years and that had over six thousand data points. These observations showed that, in my sample of deciduous trees, budburst occurred about a day earlier every year from 2006 to 2021. There are two particular points in which my data set is important. First, they come from Oklahoma, near the southwestern extreme of the deciduous forests, while most data sets are from the northeast United States or from Europe. Second, my data are longitudinal; that is, I kept track of the same trees for sixteen years. This is longer than the lifetime of any research grant; but my research required no funding. I just kept data sheets about budburst times on the trees near where I lived and worked.

The saying goes, Extraordinary claims require extraordinary evidence. But my claims were not extraordinary. They are the same as everyone else’s, even though they were based on an entirely separate data set. If my observations were different from everyone else’s, they might be suspect. But my conclusions are the same as those of nearly everyone else who has studied the changes in spring budburst resulting from global warming. As such, my conclusions are not particularly surprising, except that the fact that the trees opened their buds a day earlier each year much surpasses most studies, in which budburst occurs a day earlier each decade.

 

This photo shows post oak (Quercus stellata) buds just beginning to open.

In the next essay, I will address some particularly interesting features of this research project, which will give us an insight into the process of scientific thinking.

Are Scientists Saving the World, Or Just Making Work for Themselves?

Ecologists have a lot to do. We are busy studying a rapidly-vanishing natural world and trying to figure out how to save it. But I am increasingly frustrated because a lot of “ecological research” is just a repackaging of what we already know, and which can have no easily-imaginable impact on saving the natural world.

What we need more of is research such as what I am now finishing—a study that demonstrates that temperate trees are opening their buds sooner in the springtime due to global warming and doing so at an amazing rate. My data set has 6,068 observations, all of which I made individually. They show that Oklahoma deciduous trees (in this case, of 22 different species) are opening their buds on the average one day earlier each year. This makes them more vulnerable to the occasional late-spring frosts such as the deep freeze that descended upon Oklahoma and Texas in February 2021. Back when buds opened in March, such a freeze might have had little effect, but buds are now opening in February, and the effect of the freeze on them was profound. I know many other scientists, such as Carol Augspurger, recently retired from the University of Illinois, who are also conducting important research.

I very much doubt that my findings, or Carol’s, would make any difference to politicians, who pay attention only to the contributions made to them by oil corporations who want us to burn baby burn as much carbon as possible, regardless of what the effects might be at some future time—or, as we now know, what the effects might be right now. Oil executives are rich and do not live where wildfires or hurricanes can harm them.

But I ran across a scientific paper—alas, there are many papers like this—in which 12 authors wrote about a phenomenon that they think they discovered called nonstationarity. [https://esajournals.onlinelibrary.wiley.com/doi/pdf/10.1002/fee.2298] What, you may ask, is nonstationarity? It is the confounding of changing properties that govern ecological phenomena. Ecological systems, they claim, are under constant change and exhibit spatially and temporally varying trends. Do you follow me? They claim that ecological research needs to accommodate spatial and temporal variability in ecological patterns and processes.

All of which we already knew. The authors just developed some new software to study it differently. No new data, no new discoveries, just a new kind of analysis that tells us the same things that we already knew. They had no new data about real trees, or real birds, or real lakes, or real oceans.

What is an example of temporal nonstationarity? The fact that tree rings are sometimes thicker and sometimes thinner. They even have a photograph of some tree rings to prove their point. We have known this for almost a hundred years. It is very interesting, but not new. They claim that their work is “key to…translating findings to local policies and practices.”

Politicians, interested only in money, would not be interested in the results of my analysis of 6,068 budbursts and their climatic correlates. But they would be utterly hostile toward the idea of professional ecologists and academics using taxpayer money to repack old news into new conglomerates. The authors list six National Science Foundation grants that went into their paper. The authors came from numerous academic institutions and even from a taxpayer-funded National Laboratory. I suspect that the main effect of this paper is to advance the academic careers of the authors. The paper was prominently published by the Ecological Society of America, the major scientific society of ecologists, which should have a better idea of what ecologists should spend our time doing.

Scientific Honesty

Scientists may not be naturally more honest than other people, but the scientific method enforces honesty when it is followed, as it usually is, at least in the underfunded ecological and organismic sciences. Actually, scientists are, on average, more honest partly because the scientific enterprise attracts honest people—that is, people who do not want their reputations tainted by dishonesty. For preachers and presidents, of course, the more taint the better. So keep grabbing that p***y, Trump! And all you evangelical Christians, keep praising Trump for doing so!

One of my major projects is that I have kept records on the spring budburst dates of almost 400 trees (22 species) for the last twelve years in southern Oklahoma. While my data set is not the biggest in the world, it is one of the major on-the-ground data sets (as opposed to satellite imagery), and certainly the best one for hundreds of miles around where I live and work. On January 30 and 31 of this year, almost all of the sweetgum trees (Liquidambar styraciflua, in the Altiginaceae family) burst their buds—that is, the bud scales separated enough that I could see the green underneath. But there was one tree I missed. It was way over across campus, not close to any other trees in my data set. Since it is surrounded by brick walls, creating a warm microenvironment, I assumed that its buds had opened also. This was a statistically valid assumption. But if I wanted to make this tree a data point (datum) in my study, I had to go look at it. I did so—it was a nice 73 degree F day, like many other winter days in southern Oklahoma (itself an indicator of global warming)—and found that, indeed, I was correct. All this, for one datum out of several thousand.

This honesty is in striking contrast to the ruling junta in Washington, where the worshipers of Donald Trump believe that they can just make up “alternative facts”, assertions that God Himself is obligated to accept. My data clearly show that budburst over the past twelve years has occurred about three weeks earlier—more in some, less in other, species. But Trump can just make up an alternative fact, and say that this has not happened, and that simply sweeps aside my thousands of data and the millions of data worldwide not only of global climate change but of organism responses to it. I fear—and I hope I am wrong—that Trump and his junta will force federal research facilities to make up data to prove that global warming is not occurring, and cut off grant funding for anyone who does not agree with Him. This won’t hurt me; I just keep records on the trees I see when I walk to work or drive down to the park. All I need is statistical software, which the university provides (don’t tell Trump). The ascendancy of “alternative facts” or Trump-truths is one reason I believe that the very scientific way of thinking is under assault in America.

Maybe not in France. They have their own political mess right now, but even the right-wingers over there appear to accept global climate change and the importance of doing something about it. There is more than one way of being wrong. You can be in error, or you can be abusively wrong. The former, in French, is se tromper (to deceive oneself) (Trump le trompe), I think. The latter is avoir tort (Trump a tort). Perhaps the best description of Trump is Trump nous trompe—Trump deceives us. He should be ashamed, but Trump n’a jamais honte.

Climate Change Workshop, part 5.

The climate change workshop for teachers, sponsored by Oklahomans for Excellence in Science Education (OESE) and the Oklahoma Climatological Survey continued this afternoon and evening.

The first two presentations were about phenology. Phenology is the seasonal pattern of biological processes: the time of year that trees burst their buds, that animals hibernate or migrate, etc. Phenological data are particularly valuable to a study of global warming because the organisms integrate many physical factors. How do you measure temperature? Average maximum temperature? Average minimum temperature? Threshold temperatures? But you can let the organisms themselves do the measuring. If global warming causes winter to be shorter and warmer, and spring to come earlier, perhaps the best way to measure this is to quantify the budburst date of deciduous trees or the flowering date of herbaceous plants.

The first presenter was Dr. Lara Souza of the University of Oklahoma and the Oklahoma Biological Survey. What happens when species experience global warming? They could either stay where they are and adapt (either through natural selection or acclimatization); go extinct; or migrate to other locations with cooler temperatures.

Consider some examples. Camille Parmesan and associates showed that some British butterflies moved north during the twentieth century. They gathered their data from insect collections, in which the date and location are recorded. Another study, by Lenoir and associates, showed that most but not all species of mountain plant species shifted their distributional range to higher elevations. You can download the Lenoir data from Science (these data are open access, unlike many of the articles in Science) and have students compare the average elevation in the early vs. the late twentieth century for each species, either by making a graph or by doing a simple statistical analysis (paired-t test). The Rocky Mountain BiologicalLaboratory, at about 10,000 feet elevation in the Rockies, also has an excellent data set about the first day in spring at which many species of birds and mammals became active; this data set stretches back to 1974. Some, but not all species, have become active much earlier in the spring in the past forty years. The RMBL website is being reconstructed, but the link should lead you to the data at a later time. Another study, led by Laura Burkle, revisited some nineteenth-century pollination study plots to see how much changes has occurred in phenology. She found that, in many cases, the plants were flowering earlier but the pollinators were arriving at the same time compared to 150 years earlier.

Lara then told us how students can contribute their own data to, or work with data sets made available by, the National Phenological Network. There are also some citizen-science projects being done, including common garden experiments where people in different places plant the same plants, and keep track of their phenological responses. With the example of lilacs, people all over the country have planted not just lilacs but exactly the same breed of lilacs so that they can make direct comparisons of the same breed of plant in very different geographic locations. (There are some limitations. For example, lilacs do not grow well in Oklahoma.) Students can participate in these citizen-science projects and contribute their data to a national database.

The Saturday evening presentation was by me. Now think about this. A group of energetic teachers who have been in a workshop for a day and a half. Should I just give them a scientific seminar? Uh, no. Especially since there is no place else for them to go except to my presentation! There used to be a bar down the highway but it closed. So it behooved me to present a standup comedy routine before getting into the science.

Standup comedy is not something entirely new to me. In June 2012, when I was staying with my sister in La Jolla, I walked past the San Diego Comedy Club, and it was open mike night. Why not? I signed my name on the list and went to get my Darwin hat. It was a pretty big audience, or so I thought. The only problem is that the real audience was only about six people, and everyone else was on the list for performing. Each person did his or her little thing, then left, so when they got to me (number 28) the room was pretty empty. Most of the routines were pretty lame, and most of them for the same reason: they talked only about themselves. I might have been the only comedian to talk about something other than himself. I didn't tell them my real name. I talked to them, instead, about hagfishes. Anyone who knows about hagfishes knows that you can get a lot of truly disgusting comedy material out of them. At the end, the emcee took a vote for best performance. I was one of two nominees. The emcee chose as the winner a third person who was not nominated. If I were a budding young comedian, I would have been bent out of shape, but I have a day job, so whatever. The audience was in the parking lot as I walked to the supermarket, and they said, "Hey, Darwin!" and told me they liked it. I told them I was a professor and I did things like this in my classes.

Then I gave my scientific presentation, which I briefly summarize here. I have nine years of data about budburst times of deciduous trees in Durant, Oklahoma, and the results clearly show that budburst has occurred earlier during the course of those nine years--not consistently every year, but clearly overall. But not in all species.

Then, I wanted to know what might happen in the future. Suppose that Oklahoma gets so warm that winter disappears altogether? Would that mean that the deciduous trees would grow new leaves as soon as they drop their old ones? (They will still drop their leaves, a process controlled by daylength.) That is, can I extrapolate my budburst data? The answer is not always. The answer is yes for sweetgum trees, whose buds are fully formed in the fall, but the answer is no for sycamores and pecans, whose buds require a period of cold temperatures in order to complete their development. This conclusion is based on research I conducted with my student Sonya Ross. Therefore, if global warming occurs so much that winter disappears, the budburst of some tree species will actually be delayed.

I let them go, but they all stayed to hear me perform my Evolution rap (which is on YouTube here) and my cowboy version of Wrangham's cooking hypothesis (which is on YouTube here). I then shared some refreshments with them. For workshop participants, as for students, they learn more when they are having fun--to an extent, anyway.

Climate Change Workshop, part 6.

The climate change workshop for teachers, sponsored by Oklahomans for Excellence in Science Education (OESE) and the Oklahoma Climatological Survey continues this morning.

The first two presentations were about phenology. Phenology is the seasonal pattern of biological processes: the time of year that trees burst their buds, that animals hibernate or migrate, etc. Phenological data are particularly valuable to a study of global warming because the organisms integrate many physical factors. How do you measure temperature? Average maximum temperature? Average minimum temperature? Threshold temperatures? But you can let the organisms themselves do the measuring. If global warming causes winter to be shorter and warmer, and spring to come earlier, perhaps the best way to measure this is to quantify the budburst date of deciduous trees or the flowering date of herbaceous plants.

I was the first presenter. I had enough time for some introductory perambulations. I told them where they could get more information about my work. And I reported what some of us had talked about over breakfast: what needs to be done to prevent global warming? My conclusion was that there was no single thing that could be done. Denialists like to consider each proposed solution--alternative energy, energy efficiency, etc.--and say that each of them are insufficient to solve the problem. They pick off each solution individually, without considering that the combined efforts on all of these things may solve the problem. But in order for us to do all of these things, we need a whole new attitude: we need to desire to be frugal with our use of resources, to recycle, to drive smaller cars. It requires a change of attitude. We can model these attitudes to people around us, many of whom may began imitating us (when they see that we are doing these things joyously) or at least no longer considering us to be quite as weird as they might have previously. But even more fundamentally, we need to think of ourselves as caretakers rather than owners not only of the Earth but of everything, even sheets of paper or plastic bottles. They are not ours to use as much as we wish; we are only the stewards of these "resources." This attitude is expressed well in the musical Nanyehi, which is based on the life of the Cherokee leader Nancy Ward (my ancestor). A white man from South Carolina tried to claim some Cherokee land, and he had the piece of paper from the colonial government of South Carolina to prove that he was the owner. When some Cherokee warriors found him, they were astonished that anyone could own land. They sang, in the musical, "This land is not our land/We're only passin' through/It don't belong to us/It don't belong to you!"

I told the group about my work with spring budburst of 22 Oklahoma deciduous tree species. Most of these species opened their buds earlier, some as much as 2 days earlier per year (compared to the typical pattern of budburst occurring 2 days earlier per decade). That is, the phenological effects of global warming are happening up to ten times faster in Oklahoma than in other parts of North America. But one species (the silver maple, Acer saccharinum) opened its buds later. The reason was not the warmer temperatures in the spring, but the heat wave and drought in the summer, which damaged the buds.

Trees cannot keep opening their buds earlier and earlier forever. How far can the trend to earlier budburst continue? If winters are too warm, some tree species will have a later budburst, not an earlier one, because cold temperatures in winter are necessary to break down inhibitors. How much winter cooling is necessary to break down those inhibitors? I have begun research to help answer these questions.

The second presenter is Dr. Lara Souza of the University of Oklahoma and the Oklahoma Biological Survey. What happens when species experience global warming? They could either stay where they are and adapt (either through natural selection or acclimatization); go extinct; or migrate to other locations with cooler temperatures.

Consider some examples. Camille Parmesan and associates showed that some British butterflies moved north during the twentieth century. They gathered their data from insect collections, in which the date and location are recorded. Another study, by Lenoir and associates, showed that most but not all species of mountain plant species shifted their distributional range to higher elevations. You can download the Lenoir data from Science (these data are open access, unlike many of the articles in Science) and have students compare the average elevation in the early vs. the late twentieth century for each species, either by making a graph or by doing a simple statistical analysis (paired-t test). The Rocky Mountain Biological Laboratory, at about 10,000 feet elevation in the Rockies, also has an excellent data set about the first day in spring at which many species of birds and mammals became active; this data set stretches back to 1974. Some, but not all species, have become active much earlier in the spring in the past forty years. Another study, by Eric Post and associates, show that the phenological patterns of arctic tundra plants have shifted dramatically, while those of caribou have not changed as much, which means that many caribou food plants are no longer available (or have older, less nutritional foliage) when the caribou need them. Therefore the caribou have fewer surviving offspring. A study by Laura Burkle and associates showed that flowering times of numerous plant species have shifted over the last 120 years, and that this has resulted in the loss of pollinator associations in many cases.

Lara then told us how students can contribute their own data to, or work with data sets made available by, the National Phenological Network. There are also some citizen-science projects being done, including common garden experiments where people in different places plant the same plants, and keep track of their phenological responses. With the example of lilacs, people all over the country have planted not just lilacs but exactly the same breed of lilacs so that they can make direct comparisons of the same breed of plant in very different geographic locations. (There are some limitations. For example, lilacs do not grow well in Oklahoma.) Students can participate in these citizen-science projects and contribute their data to a national database.

This morning the participants learned about both a whole new way of understanding and teaching about global warming.

Reality of Global Warming: The Phenology 2012 Conference

I am in Milwaukee, where the Phenology 2012 conference has just ended, except for a field trip to a bog tomorrow. It is a small but powerful conference, with scientists and science students from 21 countries. It is one of the most remarkable conferences I have attended. Thanks go to Mark Schwartz at the University of Wisconsin at Milwaukee, who has been one of the world leaders in phenology research for decades—his hard work made this conference a success in every detail.

Phenology is the study of seasonal patterns of organisms: buds bursting in spring, leaves falling in autumn, animals migrating, etc. This is part of the adaptations that organisms have: they have physiological mechanisms that allow them to do the right things at the right times.

Phenology is not only an international science but an interdisciplinary one. Some of the conference participants study satellite data, which show “greening-up” occurring earlier each year, while others study organisms directly. The interdisciplinary nature of the subject is also what has made this a remarkable conference. We also heard from scientists who specialize in citizen science: they coordinate the efforts of ordinary citizens to collect seasonal data about plants and animals, and put these data into an organized database (see the USA National Phenology Network). We heard from educators who involve the public in phenology awareness.

I gave a presentation in which I documented that the Oklahoma trees I have been watching for the last seven years are, in most cases, opening their buds one to two days earlier each spring, which demonstrates a remarkable rate of global warming. The one exception is silver maples, which (in my sample) all died in the 2011 heat wave. This rate cannot continue; if winters become too warm, the buds will actually open later, not earlier, because cold weather is required to break down their inhibitors (inhibitors are sort of like hibernation hormones).

A couple of years ago, Senator Jim Inhofe from my state of Oklahoma issued a list of climate scientists who should be investigated by the Department of Justice for possible criminal activity because they study global warming at taxpayer expense. Since global warming cannot be happening, Inhofe reasons, these scientists must be making stuff up. One of the scientists on Inhofe’s list is Thomas Karl, our keynote speaker, who did not know he was on the list until I told him. Way to go, Oklahoma. But I think all of us who study phenology should also be on the list. (Technically, I would not be on the list, because I have never received funding for my phenology studies.) I began my talk, “Dear fellow criminals…” That got their attention.

I met two scientists (Steven Running and Kirsten DeBuers) who fully accept global warming, but who wrote a paper that indicated that some trees (up in the mountains) would grow more under warmer temperatures. A global-warming-denial website put them on the list of 3000 “scientists who deny global warming.” So don’t believe these lists, folks! Many of the scientists on these lists were put there falsely!

I also met the woman who blogs about global warming for Huffington Post. You can follow her on Twitter at @climategeek.

What does this topic have to do with evolution, the usual topic of this blog? In the past, normal ecological and evolutionary processes allowed organisms to respond to global climate changes because these changes occurred slowly. Organisms could, over the course of thousands of years, migrate: birds could fly, mammals could run, and seeds could be carried by animals or wind. Over the course of millions of years, organisms could evolve in response to climate changes, such as the spread of grasslands about thirty million years ago. But global climate changes, as great as almost any of those, are occurring today over the course of decades and centuries, too fast for either migration or evolution to adjust. In addition, today, there are roads, cities, and farms in the way. If the ocean rises you can’t just move inland—somebody else already owns the land there. Phenology, therefore, is an important field of study. It shows us that the current rapid rate of global warming is causing remarkable changes in the seasonal activities of organisms. These changes serve as a warning to us about what is going to happen, imminently, in our future.

Back in the days of Gilbert White, phenology was a pleasantly peaceful science. White wrote about the arrival and departure of birds, the opening of buds, and the emergence from hibernation of his female turtle Timothy. Phenology did not rock the world the way evolution did. This is no longer true. Scientists all over the world are documenting that plants and animals are responding to global warming. Ordinary people cannot see carbon dioxide. But they can see that buds that used to always open in April are now opening in March, and doing so nearly every year. They are telling us that global warming is occurring, however much Senator Inhofe insists that it is not.