Climate Change and Phenology

Content
		¬
		Background readings   Forrest and Miller-Rushing (2010) Toward a synthetic understanding of the role of phenology in ecology and evolution Miller-Rushing and Primack (2008) Global warming and flowering times in Thoreau's Concord: A community perspective    
		¬
		Introduction    
		  Herbarium 
		    
		  specimens 
		    
		  reveal 
		    
		  the 
		    
		  footprint 
		    
		  of 
		    
		  climate 
		    
		  change 
		   
		  on 
		    
		  flower 
		   
		  ing 
		    
		  trends 
		    
		  across 
		    
		  nort 
		   
		  h-central 
		    
		  North 
		    
		  America 
		  Climate change as a result of anthropogenic greenhouse gas (GHG) emissions is clear in both climatological and biological data.  Global temperatures have increased by 0.74°C ± 0.18°C over the past 100 years (1906-2005), although some regions experience locally greater warming (IPCC 2007).  Along with this average increase in temperature, extreme weather events including extreme heat have become more common.  The ten hottest years on record have all occurred since 1998. Scientists use long-term climate and biological datasets to assess past and current rates of warming and the impacts of this warming on key ecosystem functions.  These analyses provide crucial information for the prediction of future impacts of warming as we continue to release massive quantities of GHGs into the atmosphere. One clear biological indicator of climate change is phenology, or the timing of key life events in plants and animals.  Phenological events are diverse and include time of flowering, mating, hibernation, and migration among many others.  Generally, phenological events are strongly driven by temperature, with warmer temperatures typically resulting in earlier occurrence of springtime migration, insect emergence from dormancy, and reproductive events.  Shifts in phenology in the direction predicted by climate change have been observed worldwide, suggesting that climate change is already having profound, geographically broad impacts on ecology (Parmesan & Yohe 2003, Menzel et al. 2006; Rosenzweig et al. 2008).   In this project you will:
	1	analyze long-term temperature data collected (in Connecticut) by the U.S. Historical Climatology Network (http://cdiac.ornl.gov/epubs/ndp/ushcn/ushcn_map_interface.html) to establish temperature trends over the past 115 years;
	2	investigate temperature effects on the flowering of six plant species (in Ohio) using the dataset from Calingern et al. (2013); and
	3	examine the ecological impacts of phenological change on the arrival/emergence times of two pollinator species for some of these flowers (using data from Ledneva et al., 2004, for Massachusetts).
		This exercise is adapted from Teaching Issues and Experiments in Ecology, Vol. 10. Data Set: Investigating the footprint of climate change on phenology and ecological interactions in north-central North America, by Kellen M. Calinger, Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH 43210-1293; kcalinger@gmail.com    
		¬
		Part 1: Temperature change and regional differences   Attached Files:
		¬ StamfordCT067970_6658.csv ¬ (36.031 KB)
		¬ StorrsCT068138_8237.csv ¬ (33.943 KB)
		¬ FallsVillageCT062658_2045.csv ¬ (33.675 KB)
		  An important component of climate change studies is the analysis of temperature change over long timescales in the region of interest.  For our analysis of Connecticut, you will assess temperature change across the entire state as well as at smaller, regional scales.  The U.S. Historical Climatology Network (USHCN) has collected temperature and precipitation data at weather stations throughout Connecticut since 1895. The number of USHCN weather stations is limited as USHCN stations are required to have a consistent, non-urban location since 1895; this eliminates urban heat island effects (urbanized areas that are hotter than surrounding rural areas, U.S. EPA) and latitudinal/altitudinal effects. Changes in the location of weather stations can cause apparent increases or decreases in temperature as a result of moving to a generally warmer or cooler location.  These possible altitudinal or latitudinal effects are eliminated in the USHCN climate record by requiring consistent station locations since the start of data collection.  Using the mean of temperatures recorded at all weather stations in Connecticut, we can evaluate statewide trends in temperature since 1895.  To assess regional trends in temperature, we can use the three climate divisions in Connecticut established by the National Oceanic and Atmospheric Administration (NOAA, see map below).  The temperature record for each climate division is given in separate Excel worksheets. The sites include Stamford (Region 1), Storrs (Region 2), and Falls Village (Region 3).  Each climate division worksheet includes four columns:
	1	"State_id" is the weather station identification code,
	2	“Year” provides the year in which the temperature data were collected,
	3	"Month" is the month coded from 1 to 12, and
	4	“TMEAN F” provides the spring time temperature for that year in degrees Fahrenheit.
		¬
		¬       
		   
		¬
		Assignment 1: Temperature trends   Attached Files:
		¬ Assignment1.docx ¬ (83.279 KB)
		  With your partner, pick two climate divisions you will analyze. If you’re from Connecticut, take a look at your home town division as one of your two climate divisions. Download and open the data files for those regions. Use the data to answer the questions in the attached worksheet.    
		¬
		Part 2: Biological Indicators of Climate Change: Flowering Time   Attached Files:
		¬ FloweringData.xlsx ¬ (40.476 MB)
		  Flowering time is a crucial phenological event for plants as it can strongly impact reproductive success (Calinger et al. 2013).  Previous research has shown significant advancement of flowering with temperature increase (called phenological responsiveness, days flowering shifted/^oC), although species vary in the degree to which they shift flowering with temperature change.  Since flowering time can have substantial fitness effects, climate change may alter species performance as climate warms, causing some species to decrease in abundance.  You will analyze data on Ohio flowering times and assess impacts of temperature increase on species diversity. Click on the worksheet labeled “Flowering data.”  This worksheet provides data on the dates of flowering for six plant species collected throughout Ohio as well as temperature data and additional descriptive data (Calinger et al. 2013).  Look at the column headings: Species, Common Name, County, Year, Division, Temperature, and DOY.  Species and Common Name specify the plant species of interest.  Each row represents an individual observation for a given species.   County and Division provide information on the county of observation and the NOAA Climate Division in which that county is found.  Year simply indicates the year in which the observation was made.     Flowering dates are given in the “DOY” column.  DOY stands for “day of year” and is the numeric day of year (day 1=Jan.1, Dec. 31=365, and so on) that the plant was flowering.  Each flowering date is paired with a temperature specific to the individual plant’s location, year, and season of observation.  This temperature (^oC) is given in the Temperature column. 
		   
		¬
		Assignment 2: Flowering times   Attached Files:
		¬ Assignment2.docx ¬ (118.301 KB)
		  Use the data from Calinger et al. (2013) to answer the questions in the attached worksheet.    
		¬
		Part 3: Biological Indicators of Climate Change: Butterfly Emergence and Hummingbird Arrival Times   Along with shifts in the timing of plant phenological events, scientists have observed significant shifts in the timing of animal phenological events such as migration, insect emergence, and mating associated with temperature increase (Cotton 2003).  Like flowering time in plants, the timing of these phenological events has direct impacts on reproductive success in animals. Further, changes in the timing of phenological events in plants and animals may disrupt important plant-animal interactions such as pollination.  These disruptions of interactions as a result of shifting phenology are called trophic mismatches.  For example, in pollination mutualisms, the pollinator benefits from pollen and nectar food resources and the plant benefits by being pollinated and increasing its reproductive success.  Under average climate conditions, without climate change associated warming, flowering time in the plant and arrival time of the pollinator (based on migration or insect emergence date) are cued to coincide.  However, if the plant or pollinator responds more strongly to climate warming and shifts their phenology more than their mutualistic partner, this relationship will be disrupted.  This trophic mismatch results in decreased pollination and reproduction for the plant and a loss of important floral food resources for the pollinator. Using data provided below, you will be assessing the effects of warming on shifts in arrival time of the migratory ruby throated hummingbird, Archilochus colubris and emergence from overwintering of the Spring Azure butterfly, Celastrina ladon (data from Ledneva et al. 2004).   Both of these species occur in Ohio although this data was collected in Massachusetts.  For this study, we will assume that the responses of both the ruby throated hummingbird and the Spring Azure butterfly are uniform throughout their ranges. You will also discuss whether we have evidence for trophic mismatches based on your findings. 
Species | Arrival Time Change (days/^oC)
Celastrina ladon (adults) | 0.55
Archilochus colubris | -1.40
		   
		¬
		Assignment 3:   Attached Files:
		¬ Assignment3.docx ¬ (112.269 KB)
		  Complete the attached worksheet using the data from Ledneva et al. (2004).    
		¬
		Literature Cited  
	1	Bertin RI. 1982. The ruby-throated hummingbird and its major food plants: ranges, flowering phenology, and migration. Canadian Journal of Zoology  60: 210-219.
	2	Calinger, K., S. Queenborough, and P. Curtis. 2013. Herbarium specimens reveal the footprint of climate change in north-central North America. Ecology Letters 16:1037–1044.
	3	Cotton, P.A. 2003. Avian migration phenology and global climate change. PNAS 100:12219-12222.
	4	IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
	5	Ledneva, A., Miller-Rushing, A.J., Primack, R.B., and Imbres, C. 2004. Climate change as reflected in a naturalist’s diary, Middleborough, Massachusetts. Wilson Bulletin 116: 224-231.
	6	Menne, M. J., Williams Jr., C. N.,  and Vose, R. S. 2010. United States Historical Climatology Network (USHCN) Version 2 Serial Monthly Dataset. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee.
	7	Menzel, A., Sparks, T.H., Estrella, N., Koch, E., Aasa, A., Ahas, R., et al. 2006. European phenological response to climate change matches the warming pattern. Global Change Biology 12:1969–1976.
	8	Parmesan, C. & Yohe, G. 2003. A globally coherent fingerprint of climate change impacts across natural systems. Nature 421:37–42.
	9	Rosenzweig, C., Karoly, D., Vicarelli, M, Neofotis, P., Wu, Q., Casassa, G., et al. 2008. Attributing physical and biological impacts to anthropogenic climate change. Nature 453:353-357.
	10	United States Environmental Protection Agency.  Heat Island Effect. [http://www.epa.gov/hiri/] Last accessed April 5, 2013.
	11	University of Florida IFAS Extesion. Butterfly Gardening in Florida. [http://edis.ifas.ufl.edu/uw057] Last accessed January 31, 2014.