1 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change 2 Supplemental Material 3 Jonathan B. Butcher1, Daniel Nover2,3, Thomas E. Johnson2, and Christopher M. Clark2 4 5 1 Tetra Tech, Inc., PO Box 14409, Research Triangle Park, North Carolina 27709; jon.butcher@tetratech.com (corresponding author), tel: 919-485-2060; fax: 919-485-8280 2 U.S. Environmental Protection Agency, Office of Research and Development, Washington, District of Columbia; Johnson.Thomas@epa.gov; Clark.Christopher@epa.gov. 3 current affiliation: U.S. Agency for International Development, West African Regional Office, Accra, Ghana; dmnover@gmail.com. Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 1 6 1 Lake Archetypes 7 The lake archetypes are defined by 3x3x3 combinations of depth, water clarity, and surface area or fetch. A key to 8 the archetypes is provided in Table S-1. 9 2 Meteorological Forcing 10 Meteorological time series for this work are a subset of those developed for a U.S. EPA modeling study of potential 11 climate impacts on hydrology and water quality in large U.S. watersheds (Johnson et al. 2012; U.S. EPA 2013). To 12 represent different baseline climate conditions we selected a set of nine first-order weather stations located in 13 different hydroclimatic regions from humid sub-tropical Tampa, FL (mean temperature 22.3 °C) to cold, high- 14 elevation Sugarloaf Reservoir, CO (mean temperature 4.6 °C). Detailed characteristics of the weather stations are 15 summarized in Table S-2, while Figure S-1 shows the range of combinations of average annual precipitation and 16 temperature covered by the set. 17 NARCCAP uses higher-resolution RCMs to dynamically downscale output from Global Climate Models (GCMs) 18 used in the Intergovernmental Panel on Climate Change (IPCC) 4th Assessment Report (IPCC 2007) to a 50x50 km2 19 grid over North America that is more appropriate for site-scale response modeling. This downscaled output is 20 archived for two 30-year periods (1971-2000 or “recent” and 2041-2070 or “mid-21st century”) at a temporal 21 resolution of three hours. The simulations use the IPCC’s A2 greenhouse gas emission scenario, which at the time 22 of development was a relatively “pessimistic” future greenhouse gas trajectory, but is now considered more middle- 23 of-the-road compared to current trends and the most recently developed scenarios. By mid-21st century, the 24 different IPCC greenhouse gas scenarios have not yet diverged much in predicted average air temperatures, so 25 impact of the choice of any one particular scenario is diminished compared to later in the century. 26 Six NARCCAP scenarios were selected to leverage time series processing for a previous study of watershed 27 response (U.S. EPA, 2013); additional scenarios have subsequently been released by NARCCAP. Table S-3 28 identifies the combinations of GCMs and RCMs included in this study. 29 Meteorological time series at an hourly time step were created using a change factor approach (Anandhi et al., 2011) 30 applied to time series from existing meteorological stations acquired from the 2006 BASINS Meteorological 31 Database (U.S. EPA, 2008). Temperature adjustments were made by adding or subtracting the monthly change 32 factors to historical daily temperature during the baseline period. Multiplicative monthly change factors were 33 applied to other meteorological variables. NARCCAP projections were interpolated to each weather station, and 34 monthly change statistics calculated for: total precipitation, air temperature, relative humidity, surface downwelling 35 shortwave radiation, and wind speed. Averages and standard deviations for the change factors are shown in Table 36 S-4. 37 It is anticipated that future climate change will result in intensification of rainfall for some, if not many, regions and 38 seasons (Groisman et al. 2005; Kundzewicz et al. 2007). More intense precipitation events projected for many areas 39 under future climate may be expected to contribute to a greater fraction of flow as direct runoff and may also cause a Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 2 40 non-linear increase in sediment erosion and pollutant loading. To address this, the projected scenario time series of 41 precipitation include changes in both monthly precipitation volume and the proportion of precipitation volume 42 occurring in larger magnitude events: Monthly change factors were applied to historical daily precipitation as 43 multipliers to increase or decrease daily values (events) in two distinct groups: one multiplier was applied to 44 precipitation events greater than or equal to the 70th percentile and a different multiplier was applied to precipitation 45 events less than the 70th percentile (see U.S. EPA, 2013 for details). In most study locations NARCCAP 46 projections suggest increases in the fraction of precipitation contained in larger events. Average precipitation and 47 temperature for each scenario is shown in Table S-5. 48 Airport wind time series (10 m observation height) are adjusted to estimate surface shear within LISSS. Airport 49 measurements from open areas are typically greater than on-lake wind due to sheltering by shoreline canopies and 50 topography. We ran simulations with and without sheltering (10 m height); in the former case using the median 51 results of Markfort et al. (2010): 52 Wstr 53 where Wstr is the wind sheltering coefficient, hc is the shelter height (m), and f is the lake fetch (m). Results 54 presented in the main text incorporate 10 m wind sheltering. 55 Several additional forcing time series for LISSS that are not directly available from the BASINS meteorological data 56 set were calculated to be consistent with the observed data. Dry air partial pressure was assumed to be 101,325 Pa at 57 sea level and adjusted by -12 Pa per meter of elevation. Atmospheric pressure of moist air was then calculated by 58 adjusting for the partial pressure of water based on humidity. Atmospheric specific humidity was derived from air 59 temperature and dew point temperature, as was atmospheric density. Direct beam solar radiation was partitioned 60 into direct and diffuse components assuming that scattering varies from 20 percent under clear skies to 70 percent 61 under fully overcast skies; these components were further divided to visible and near infrared bands based on the 62 average fractions given in ASTM Standard G173 (2012) reference spectrum AM 1.5D. Earth orbital parameters 63 were held constant at 1995 values. 64 One of the larger sources of uncertainty in specifying energy forcing based on surface observations is the estimate of 65 incoming (downward) longwave radiation (Prata, 1996). Flerchinger et al. (2009) reviewed the many different 66 equations proposed for clear sky emissivity and cloud corrections and recommended the use of the method of Dilley 67 and O’Brien (1998) or Prata (1996) for emissivity. We implemented the Prata method because, while reported to 68 have somewhat greater root mean squared error it also had less bias than the Dilley and O’Brien method in the tests 69 of Flerchinger et al. This was combined with the Keding (1989) correction for cloud cover. 70 Finally, aerosol deposition on snow, especially black carbon deposition, has an important effect on cold-region 71 energy balance and the longevity of snow insulation on lakes. Aerosol deposition can vary significantly from year 72 to year due to changes in fire intensity, volcanic eruptions, and anthropogenic emissions. For our study we hold 50 hc 100 hc cos 1 2 f f 2 f 2 50 hc , 2 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 3 73 aerosol deposition rates constant by month using gridded monthly mean results for 2000 conditions available with 74 the CLM4 model. 76 3 Correlation of Results with Lake Characteristics and Climate Forcing 77 General results of the simulations with future climate are presented in the main paper. An example of the detailed 78 output of the model is shown in Figure S-2. Figure S-3 shows the changes in surface water temperature, while 79 Figure S-4 shows changes in average days per year with ice cover. 80 We investigated the relationship of projected water temperature to lake characteristics (archetype) and climate 81 forcing variables through the use of analysis of variance (ANOVA), Pearson correlation analysis, and Classification 82 and Regression Trees (CART). The archetype characteristics (Table S-1) are categorical variables, amenable to 83 ANOVA analysis (Table S-6). Across all sites, the depth-integrated average annual water temperature and bottom 84 temperature are negatively associated with maximum depth and fetch and positively associated with Secchi depth 85 (water clarity). Surface water temperature is not significantly associated with water depth or Secchi depth, but has a 86 negative correlation with fetch (under wind-sheltered conditions), as larger fetch results in greater mixing of water 87 away from the surface. Maximum depth x Secchi depth was the only significant second order interaction. 88 Table S-6 shows how water temperature is correlated with lake characteristics, but does not directly inform sources 89 of sensitivity to change. On repeating the ANOVA for projected changes in water temperature from recent 90 conditions to mid-21st century conditions, fetch drops out as a significant factor for depth-integrated and bottom 91 water temperatures, reflecting the lack of consistent predicted changes in wind speed for the future climate scenarios 92 (Table S-7). 93 Pearson correlations between average annual changes in climate variables and average annual changes in 94 temperature response are shown in reduced form in Table S-8. Note the strong correlation among some of the 95 climate variables in the lower half of the table. For example, dew point temperature has a positive correlation with 96 atmospheric temperature and precipitation, and a negative correlation with solar radiation, resulting in strong 97 correlations between dew point and water temperature. 98 CART, which applies a hierarchical procedure to evaluate which variables have the greatest power to distinguish 99 sets and subsets of data into distinct groups, provides further insight into the relationships between atmospheric 75 100 forcing and in-lake effects. The top two factors for describing change in surface water temperature are, not 101 surprisingly, the change in atmospheric temperature and solar radiation, while the factors best discriminating change 102 in bottom water temperature are depth, change in atmospheric temperature, and change in wind. 103 LISSS simulations with smaller fetch are predicted to have less vertical mixing and greater longwave and sensible 104 heat loss back to the atmosphere, but lesser latent heat loss. Under wind sheltered conditions the total heat loss is 105 greater for lakes with larger fetch, as the change in latent heat loss outweighs the changes in longwave and sensible 106 heat loss. This in turn results, on average, in somewhat lower annual average temperatures throughout the water Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 4 107 column for lakes with larger fetch and a negative correlation between fetch and bottom water temperature. 108 However, as wind increases in the absence of sheltering the latent heat loss increases and converges for all 109 archetypes, resulting in less difference in total heat content as a function of fetch and no significant correlation with 110 bottom water temperature.. The predicted impact of differences in fetch on vertical mixing in LISSS is small. Subin 111 et al. (2012) noted that LISSS “model predictions were relatively insensitive even to extreme changes in the fetch… 112 despite the simulated dependence of the momentum roughness length on fetch.” This may be because the model 113 also simulates the effective roughness length as being larger for small fetch where the waves have not had a chance 114 to equilibrate with the mean forcing wind. Wind on most lakes is less than reported at nearby airport stations due to 115 a combination of vegetative and topographic sheltering, so the wind-sheltered projections are more generally 116 applicable. 117 The changes in summer Schmidt stability and annual stratification ratio vary by lake archetype, especially depth and 118 water clarity (see Table S-9). Deeper and clearer lakes tend to have less change in the annual stratification ratio 119 (fraction of time stratified) and greater changes in summer stability. For both measures there is a significant 120 interaction between Secchi depth and lake depth, reflecting the importance of energy penetration past the 121 thermocline. Pearson correlations between climate variables and stratification and mixing measures are shown in 122 Table S-10. All the stratification and mixing measures are positively correlated with air temperature and insolation. 123 Dew point is also correlated with summer Schmidt stability, stratification ratio, and August thermocline depth – due 124 to the strong correlation between air temperature and dew point – but not with the count of mixing events, as lower 125 dew point may cause greater diel evaporative cooling of the surface layer that induces mixing. For summer Schmidt 126 stability, CART analysis suggests that changes in water clarity (Secchi depth) is also an important factor in shallow 127 lakes and deep lakes, while wind is an important factor in medium depth and deep lakes. 128 4 Energy Balance: Feedback with Climate 129 The projected warming of lakes results from changes in net energy exchanges with the atmosphere. These can in 130 turn have a feedback effect on local climate. Figure S-5 shows the average annual energy exchanges simulated 131 between the atmosphere and lakes, with a positive sign indicating transfer to the lake. At the annual scale longwave 132 heat exchanges dominate, while sensible heat is important within the year. For all lakes, incoming and outgoing 133 longwave radiation increase, with a larger change in the incoming component. The latent heat balance is negative 134 and is increasingly negative in the mid-21st century, reflecting greater evaporative cooling. Together these terms 135 express an ameliorative effect of lakes on the heat balance of the surrounding land area – given sufficient flow to 136 maintain the constant lake volume assumed in the 1D model. The change in solar radiation absorbed varies by 137 climate station and depends on whether more or less cloud cover is predicted for future climate. 138 5 Sensitivity to Continued Warming beyond the Mid-21st Century 139 Climate warming is expected to continue throughout the century. In addition to the mid-21st century scenarios 140 examined in the main paper we also conducted sensitivity analyses to evaluate response to atmospheric temperature Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 5 141 increases outside the range of mid-21st century projections. These sensitivity analyses were constructed by applying 142 a fixed additive change factor (up to 10 °C) to the temperature series in the nine baseline climate series described 143 above. To ensure that the scenarios were physically realistic, dew point temperature and absolute humidity were 144 manipulated such that relative humidity was maintained at existing levels. We ran these analyses using a single lake 145 archetype set, with medium depth, medium surface area, and medium water clarity. Other climate variables were 146 held constant at existing levels. 147 Average projected summer surface water temperature is strongly coupled to air temperature with similar increases at 148 all sites of about 0.8 °C in water temperature for each 1 °C increase in air temperature with wind sheltering and 149 about 0.5 degrees per degree without. The depth-integrated average annual air temperature shows a similar rate of 150 increase for the warmer sites that lack ice cover under current conditions, but the projected rate of change is only 151 about 0.3 °C per °C of air temperature increase for the colder sites that maintain some ice cover (Figure S-6, panel 152 a). The stratification ratio increases strongly for sites that are currently stratified less than 300 days per year (panel 153 b), while days of ice cover is projected to drop sharply, although none of the sites is projected to completely lose ice 154 cover with air temperature increases up to 10 °C (panel c). 155 6 Detailed Results for Bottom Temperature Projections 156 Table S-11 contains the numerical results that correspond to Figure 1 in the main document. Results are 36-year 157 averages of bottom water temperature projected by the model. 158 7 References for Supplementary Material 159 Anandhi, A, A. Frei, D.C. Pierson, E.M. Schneiderman, M.S. Zion, D. Lounsbury, and A.H. Matonse. 2011. 160 Examination of change factor methodologies for climate change impact assessment. Water Resour Res 47: 161 W03501, doi:10.1029/2010WR009104 162 ASTM Standard G173. 2012. Standard tables for reference solar spectral irradiances: Direct normal and 163 hemispherical on 37° tilted surface. ASTM International. 164 Dilley, A.C., and D.M. O’Brien. 1998. Estimating downward clear sky long-wave irradiance at the surface from 165 screen temperature and precipitable water. Q J Roy Meteor Soc 124: 1391-1401, doi:10.1002/qj.49712454903 166 Flerchinger, G.N., W. Xaio, D. Marks, T.J. Sauer, and Q. Yu. 2009. Comparison of algorithms for incoming 167 atmospheric long-wave radiation. Water Resour. Res. 45: W03423, doi:10.1029/2008WR007394 168 Groisman, P., R. Knight, D. Easterling, T. Karl, G. Hegerl, and V. Razuvaev. 2005. Trends in intense precipitation 169 in the climate record. J Climate 18: 1326-1350, doi:10.1175/JCLI3339.1 170 Keding, I. 1989. Klimatologische Untersuchung über die atmosphärische Gegenstrahlung und Vergleich von 171 Berechnungsverfahren anhand langjähriger Messungen im Oberrheintal. Berichte des Deutschen Wetterdienstes, 172 178. Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 6 173 Markfort, C.D., A.L.S. Perez, J.W. Thill, D.A. Jaster, F. Porté-Agel, and H.G. Stefan. 2010. Wind sheltering of a 174 lake by a tree canopy or bluff topography. Water Resour Res 46: W03530, doi:10.1029/2009WR007759 175 Poole HH, Atkins RG. (1929) Photo-electric measurements of submarine illumination. J Marine Biol Assoc U K 176 16: 297-324, doi:10.1017/S0025315400029829 177 Prata, A.J. 1996. A new long-wave formula for estimating downward clear-sky radiation at the surface. Q J Roy 178 Meteor Soc 122: 1127-1151, doi: 10.1002/qj.49712253306 179 Subin ZM, Riley WJ, Mironov D. (2012) An improved lake model for climate simulations: Model structure, 180 evaluation, and sensitivity analyses in CESM1. J Adv Model Earth Syst 4: M02001, doi:10.1029/2011MS000072, 181 2012 182 U.S. EPA (Environmental Protection Agency). 2008. Using the BASINS meteorological database―version 2006. 183 BASINS Technical Note 10. Office of Water. 184 U.S. EPA (Environmental Protection Agency). (2008) Using the BASINS meteorological database―version 2006. 185 BASINS Technical Note 10. Office of Water. 186 U.S. EPA (Environmental Protection Agency). 2009a. National lakes database: A collaborative survey of the 187 nation’s lakes. EPA 841-R-09-001. Office of Water and Office of Research and Development. 188 U.S. EPA (Environmental Protection Agency). 2013. Watershed modeling to assess the sensitivity of streamflow, 189 nutrients, and sediment loading to potential climate change and urban development in 20 U.S. Watersheds. 190 EPA/600/R12/058F. National Center for Environmental Assessment, Office of Research and Development. 191 192 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 7 193 194 Supplemental Tables Table S-1. Lake Archetypes and Representative Dimensions # Maximum Depth (Hmax, m) Fetch (F, m) Equivalent Surface Area (As, m2) Geometry Ratio (As0.25 Hmax-1) 1 Short (504.6) 2 0.2 · 106 5.3 3 4 5 Shallow, Hmax = 4.0 m Medium (1471.2) 1.7 · 10 6 9.0 6 7 Long (3568.2) 8 10.0 · 10 6 14.1 9 10 Short (504.6) 11 0.2 · 106 5.3 12 13 14 Medium, Hmax = 13.0 m Medium (1471.2) 1.7 · 10 6 9.0 15 16 Long (3568.2) 17 10.0 · 106 14.1 18 19 Short (504.6) 20 0.2 · 10 6 5.3 21 22 23 Deep, Hmax = 24.0 m Medium (1471.2) 1.7 · 10 6 9.0 24 25 26 27 195 196 197 198 199 200 201 Long (3568.2) 10.0 · 106 14.1 Water Clarity; Secchi Depth (SD, m) NLD Count Turbid (1.2) 256 Moderate (2.5) 81 Clear (4.5) 96 Turbid (1.2) 94 Moderate (2.5) 27 Clear (4.5) 47 Turbid (1.2) 79 Moderate (2.5) 23 Clear (4.5) 36 Turbid (1.2) 82 Moderate (2.5) 30 Clear (4.5) 28 Turbid (1.2) 40 Moderate (2.5) 8 Clear (4.5) 19 Turbid (1.2) 31 Moderate (2.5) 5 Clear (4.5) 7 Turbid (1.2) 62 Moderate (2.5) 21 Clear (4.5) 22 Turbid (1.2) 22 Moderate (2.5) 4 Clear (4.5) 5 Turbid (1.2) 13 Moderate (2.5) 5 Clear (4.5) 5 Notes: NLD Count represents the count of lakes with valid maximum depth, area, and Secchi depth contained in the National Lakes Database (U.S. EPA, 2009a) after sorting to the closest archetype (e.g., lakes are assigned to the “shallow” category if the maximum reported depth is less than or equal to 8. 5 m, the mid-point between the shallow and medium depth representative dimensions. Fetch length for wind stress calculation is converted to an equivalent circular area in the table. The interaction of maximum depth and surface area also defines the geometry ratio (As0.25 Hmax-1) for each case. Secchi depth is converted to a light extinction coefficient, ε (m-1), using the approximation of Poole and Atkins (1929): ε = 1.7 SD-1. Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 8 202 Table S-2. Weather Stations Study Area Station Station Name Central Arizona AZ026323 Payson, Arizona Minnesota River MN218323 New England Coastal Elevation (m) Mean Temperature (C) Annual Precipitation (cm) 1,497 13.4 56 Tracy, Minnesota 428 6.8 68 NH275780 New Durham 3 NNW, New Hampshire 195 8.0 111 Southern California CA045114 Los Angeles Intl. AP, California 30 16.9 32 South Platte CO058064 Sugarloaf Reservoir, Colorado 2,968 4.6 43 Tampa Bay FL088788 Tampa WSCMO AP, Florida 6 22.3 105 Trinity River TX412242 TX412404 Dallas Love Field, Texas Denton, Texas 134 192 19.4 17.9 94 97 Willamette River OR352709 Eugene Mahlon Sweet Field, Oregon 108 11.2 129 Tongue and Powder Rivers MT244442 Ismay, Montana 762 7.7 32 203 204 205 206 207 Note: Precipitation and temperature averages are for 1971-2000 as contained in the reprocessing of National Climatic Data Center files for the BASINS meteorological data set (U.S. EPA, 2008). For the Trinity River study area we combined two stations, using precipitation and temperature scenarios developed for Denton, Texas along with a more complete range of additional meteorological variables available at nearby Dallas Love Field, Texas. 208 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 9 209 Table S-3. GCMs and RCMs for NARCCAP Climate Scenarios Scenario 0 1 GCM RCM 2 3 4 5 6 CGCM3 HadCM3 GFDL GFDL CGCM3 CCSM CRCM HRM3 RCM3 GFDL hires RCM3 WRFP observed 210 211 212 GCMs CGCM3: http://www.ec.gc.ca/ccmac-cccma/default.asp?lang=En&n=4A642EDE-1 213 214 HADCM3: 215 216 GFDL: 217 218 CCSM: 219 220 221 222 Geophysical Fluid Dynamics Laboratory GCM http://www-pcmdi.llnl.gov/ipcc/model_documentation/GFDL-cm2.htm Community Climate System Model http://www-pcmdi.llnl.gov/ipcc/model_documentation/CCSM3.htm RCMs CRCM: Canadian Regional Climate Model http://www.ec.gc.ca/ccmac-cccma/default.asp?lang=En&n=4A642EDE-1 RCM3: 225 226 HRM3: 227 228 WRFG: 231 232 Hadley Centre Coupled Model, version 3 http://www-pcmdi.llnl.gov/ipcc/model_documentation/HadCM3.htm 223 224 229 230 Third Generation Coupled Global Climate Model Regional Climate Model, version 3 http://users.ictp.it/~pubregcm/RegCM3/ Hadley Region Model 3 http://precis.metoffice.com/ Weather Research and Forecasting Model http://www.wrf-model.org/index.php GFDL hi-res: Geophysical Fluid Dynamics Laboratory 50-km global atmospheric timeslice http://www-pcmdi.llnl.gov/ipcc/model_documentation/GFDL-cm2.htm 233 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 10 234 235 Table S-4. Summary of Change Factors for Mid-21st Century Climate Simulations at Selected Weather Stations Variable Change Factor Type Average Factor Standard Deviation Air Temperature (C) Additive 2.37 0.81 Precipitation % Change 1.25 23.47 Dewpoint (C) Additive 1.92 0.79 Solar Radiation % Change -0.57 3.27 Wind % Change -1.04 3.53 236 237 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 11 238 Table S-5. Air Temperature and Precipitation Statistics for Recent and Mid-21st Century Climate Scenarios Mid-21st Century: GCM/RCM Recent (1970 – 2005 data) CGCM3/ CRCM HADCM3/ HRM3 GFDL/ RCM3 GFDL/ GFDL hi-res CGCM3/ RCM3 Air Temperature (°C) 13.1 15.8 15.9 15.5 15.7 15.7 15.6 Precipitation (cm/yr) 56.2 49.1 54.0 60.1 50.8 53.8 49.6 Air Temperature (°C) 16.9 18.9 18.8 18.9 18.4 19.1 18.8 Precipitation (cm/yr) 34.6 33.4 43.0 32.9 33.9 34.2 30.3 4.9 7.7 7.6 7.1 8.0 7.5 7.7 Precipitation (cm/yr) 41.9 38.3 40.6 46.5 40.5 44.9 40.5 Air Temperature (°C) 22.3 24.1 24.4 24.2 24.5 24.1 24.0 112.9 108.2 128.8 119.3 107.8 126.0 93.1 7.7 10.8 10.6 9.9 10.5 10.3 10.4 67.9 69.0 72.0 75.2 66.9 74.1 73.9 7.6 10.3 10.6 9.7 10.1 10.0 9.9 31.6 32.1 31.2 35.4 28.3 35.1 42.5 7.9 10.7 10.6 10.2 10.3 10.5 10.4 113.2 120.2 126.3 120.7 121.5 119.4 113.2 11.3 13.3 13.6 12.8 12.8 13.2 13.2 120.2 127.1 118.4 118.5 109.0 125.4 113.4 Air Temperature (°C) 17.9 20.4 20.6 20.1 20.4 20.1 20.5 Precipitation (cm/yr) 97.4 89.5 104.4 92.7 76.0 100.1 105.9 Weather Station CCSM/ WRFG AZ026323 CA045114 CO05806 Air Temperature (°C) FL088788 Precipitation (cm/yr) Air Temperature (°C) MN218323 Precipitation (cm/yr) Air Temperature (°C) MT244442 Precipitation (cm/yr) Air Temperature (°C) NH275780 Precipitation (cm/yr) Air Temperature (°C) OR352709 Precipitation (cm/yr) TX412404/ TX412242 239 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 12 240 241 242 243 Table S-6. ANOVA for Lake Archetype Effect on Water Temperature Treatment Depth-Integrated Water Temperature Surface Water Temperature Bottom Water Temperature Maximum Depth -, p < 0.001 NS, p = 0.876 -, p < 0.001 Fetch -, p = 0.037 -, p < 0.001 -, p = 0.008 Secchi Depth +, p < 0.001 NS, p = 0.991 +, p < 0.001 Interaction: Max Depth x Secchi Depth -, p = 0.018 NS -, p < 0.001 Note: Results show sign of trend and probability level for scenario runs with wind sheltering. NS indicates not significant at 5% level. 244 245 246 247 248 Table S-7. ANOVA for Lake Archetype Effect on Water Temperature Change for mid-21st Century Treatment Change in DepthIntegrated Water Temperature Change in Surface Water Temperature Change in Bottom Water Temperature Maximum Depth -, p < 0.001 NS, p = 0.680 -, p < 0.001 Fetch NS, p = 0.037 -, p < 0.001 NS, p = 0.439 Secchi Depth +, p < 0.001 NS, p = 0.755 +, p < 0.001 Interactions NS NS NS Note: Results show sign of trend and probability level for scenario runs with wind sheltering. NS indicates not significant at 5% level. 249 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 13 250 251 Table S-8. Pearson Correlations for Change in Lake Water Temperature Response versus Change in Annual Average Climate Variables Air Temp. (C) Dew point (C) Precipitation (%) Insolation (%) Wind (%) Air Temp. (C) Dew point (C) Precipitation (%) Insolation (%) Wind (%) Integrated Water Temperature (C) Bottom Temperature (C) Surface Temperature (C) Jan-Mar Surface Temperature (C) Jul-Sep Surface Temperature (C) -0.205 -0.285 0.594 -0.172 0.638 -0.192 -0.256 0.540 -0.129 0.558 -0.191 -0.224 0.223 -0.171 0.349 0.202 0.207 -0.013 0.120 -0.138 0.174 0.161 0.270 0.192 0.301 Air Temp. (C) Dew point (C) Precipitation (%) Insolation (%) Wind (%) 1.000 0.242 1.000 -0.038 0.667 1.000 -0.165 -0.482 -0.278 1.000 0.288 -0.097 -0.019 0.262 1.000 252 253 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 14 254 255 Table S-9. ANOVA for Lake Archetype Effect on Change in Stratification Strength Treatment Change in Stratification Ratio Change in Schmidt Stability (May – October) Maximum Depth -, p < 0.001 +, p < 0.001 Fetch NS, p =0.585 -, p =0.037 Secchi Depth -, p < 0.001 +, p <0.001 Significant Interactions Secchi Depth x Maximum Depth (p < 0.001) Secchi Depth x Maximum Depth (p <0.001) Note: Results show sign of trend and probability level. Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 15 256 Table S-10. Pearson Correlations for Annual Average Climate Variables and Lake Stratification and Mixing Measures Air Temperature Precipitation Dewpoint Insolation Wind Stratification Mixing Event Ratio Count Schmidt Stability (May-Oct) Air Temperature 1.000 Precipitation 0.254 1.000 Dewpoint 0.900 0.439 1.000 Insolation 0.530 -0.379 0.193 1.000 Wind 0.064 -0.189 0.054 -0.124 1.000 Stratification Ratio 0.243 0.104 0.211 0.132 -0.023 1.000 Mixing Event Count 0.065 -0.027 -0.042 0.190 -0.043 -0.642 1.000 Schmidt Stability (May-Oct) 0.263 0.104 0.229 0.141 0.099 0.722 -0.503 1.000 August Thermocline Depth 0.214 -0.074 0.182 0.222 -0.113 0.404 -0.162 0.407 August Thermocline Depth 1.000 257 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 16 258 Table S-11. Detailed Results for Projected Average Bottom Water Temperature (°C) 259 See Table S-1 for Lake Archetype key, Table S-2 for weather stations, and Table S-3 for climate scenario key Weather Site Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL Tampa, FL New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH Lake Archetype 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 29.9 33.5 33.8 28.8 32.6 33.0 28.5 31.9 32.2 17.8 19.4 24.5 16.5 18.1 23.2 15.8 17.3 22.3 15.2 16.8 18.8 14.0 15.3 17.2 13.7 14.6 16.5 16.8 27.0 28.2 16.7 26.2 27.8 17.5 25.7 27.3 4.3 5.0 7.9 4.3 5.0 7.9 1 31.5 35.2 35.5 30.4 34.4 34.7 30.1 33.7 34.0 19.0 20.7 25.8 17.6 19.4 24.6 17.1 18.6 23.7 16.2 17.9 20.0 14.9 16.4 18.4 14.5 15.7 17.7 18.8 29.9 31.2 18.5 29.1 30.8 19.3 28.6 30.3 4.5 5.2 8.5 4.5 5.2 8.4 Climate Scenario 2 3 31.6 31.7 35.3 35.7 35.6 36.0 30.4 30.5 34.5 34.9 34.8 35.2 30.1 30.3 33.8 34.2 34.1 34.5 19.1 19.2 20.9 20.8 26.1 25.9 17.8 17.8 19.6 19.5 24.8 24.6 17.2 17.2 18.9 18.7 23.9 23.7 16.3 16.3 17.9 17.9 20.2 20.1 15.0 15.1 16.7 16.5 18.7 18.6 14.7 14.7 16.0 15.8 17.9 17.8 18.6 18.4 29.6 29.2 30.9 30.3 18.4 18.2 28.7 28.4 30.5 30.0 19.2 18.8 28.2 27.9 30.0 29.4 4.4 4.4 5.2 5.2 8.5 8.4 4.6 4.5 5.2 5.1 8.4 8.3 4 31.7 35.0 35.3 30.5 34.3 34.6 30.2 33.6 33.9 19.5 21.1 26.2 18.2 19.8 25.0 17.4 19.0 24.1 16.5 18.1 20.4 15.3 16.8 18.8 14.9 16.1 18.1 18.3 29.3 30.6 18.1 28.5 30.2 18.8 28.0 29.7 4.4 5.1 8.3 4.4 5.1 8.2 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 5 31.5 35.1 35.4 30.3 34.3 34.7 30.0 33.6 34.0 19.2 20.7 25.8 17.6 19.3 24.5 17.1 18.6 23.7 16.3 17.9 20.1 15.0 16.4 18.5 14.6 15.9 17.7 18.7 29.5 30.7 18.4 28.7 30.4 19.0 28.2 29.8 4.4 5.2 8.6 4.5 5.2 8.5 6 31.5 35.1 35.4 30.3 34.2 34.6 30.0 33.5 33.8 19.1 20.8 25.9 17.7 19.5 24.6 17.1 18.8 23.7 16.2 17.9 20.1 15.0 16.5 18.5 14.6 15.9 17.8 18.5 28.9 30.1 18.1 28.1 29.7 18.8 27.6 29.2 4.4 5.2 8.6 4.6 5.2 8.4 17 Weather Site New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH New Durham, NH Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Tracy, MN Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Lake Archetype 16 17 18 19 20 21 22 23 24 25 26 27 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 1 2 3 4 5 6 0 1 4.7 5.2 8.0 4.5 4.0 4.1 4.0 3.9 4.1 3.9 3.9 4.1 18.0 28.9 29.9 18.0 27.1 28.4 20.4 26.5 27.5 4.3 5.0 8.2 4.5 5.1 8.1 5.7 6.0 8.7 4.2 4.0 4.1 3.9 4.0 4.1 4.1 4.1 4.2 26.0 33.9 34.2 25.0 32.0 32.5 4.8 5.4 8.5 4.4 3.9 4.1 4.2 4.0 4.1 4.0 4.0 4.2 19.6 31.6 32.8 19.6 29.9 31.4 21.9 29.3 30.5 4.4 5.2 8.6 4.7 5.3 8.5 6.0 6.4 9.2 4.2 3.9 4.1 3.9 4.0 4.1 4.2 4.2 4.3 28.2 36.3 36.6 27.1 34.4 34.9 Climate Scenario 2 3 4.9 4.8 5.4 5.3 8.5 8.4 4.4 4.3 4.0 3.9 4.1 4.1 4.2 4.0 4.0 4.2 4.1 4.1 4.0 4.0 4.0 3.9 4.2 4.2 19.8 19.3 31.9 31.3 33.2 32.5 19.7 19.1 30.1 29.5 31.6 31.0 22.2 21.6 29.5 28.9 30.7 30.1 4.4 4.4 5.2 5.1 8.7 8.5 4.7 4.6 5.3 5.2 8.6 8.4 6.0 5.8 6.4 6.1 9.3 8.9 4.3 4.4 4.0 3.9 4.1 4.1 3.9 3.9 3.9 3.9 4.1 4.1 4.1 4.1 4.2 4.1 4.3 4.3 28.2 27.7 36.8 35.8 37.1 36.1 27.0 26.6 34.7 34.0 35.2 34.5 4 5 6 4.7 5.3 8.3 4.1 3.9 4.1 4.0 4.0 4.1 4.0 3.9 4.2 19.2 31.4 32.8 19.2 29.5 31.0 21.9 28.9 30.0 4.3 5.1 8.4 4.6 5.2 8.3 5.8 6.2 8.9 4.2 4.0 4.1 3.9 3.9 4.1 4.1 4.1 4.3 27.8 35.7 36.0 26.8 33.8 34.3 4.8 5.4 8.5 4.5 4.0 4.1 4.0 4.0 4.1 4.0 4.0 4.2 19.4 30.9 31.9 19.3 29.1 30.5 21.6 28.5 29.6 4.4 5.2 8.6 4.7 5.3 8.6 5.9 6.3 9.1 4.2 4.0 4.1 3.9 3.9 4.1 4.1 4.1 4.3 27.7 35.4 35.7 26.6 33.5 33.9 4.8 5.4 8.4 4.4 3.9 4.1 4.0 4.2 4.1 4.0 4.0 4.2 19.1 30.6 31.8 19.0 28.9 30.4 21.7 28.4 29.5 4.5 5.2 8.5 4.6 5.3 8.4 5.8 6.2 9.0 4.3 4.0 4.1 3.9 4.0 4.1 4.1 4.1 4.3 28.1 35.4 35.8 26.9 33.7 34.2 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 18 Weather Site Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Dallas, TX Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Ismay, MT Lake Archetype 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 0 26.6 31.1 31.6 9.2 11.0 16.6 7.9 9.5 14.8 8.8 9.7 14.5 8.3 9.1 10.7 6.3 7.4 8.6 6.5 6.7 7.9 17.2 27.5 28.2 17.3 25.3 26.3 19.8 24.4 25.3 4.3 5.0 8.1 4.5 5.1 8.0 5.8 6.1 8.6 4.1 3.9 4.1 4.0 3.9 4.1 1 28.8 33.4 33.9 11.0 12.7 18.4 9.5 11.1 16.6 10.3 11.3 16.2 9.9 10.9 12.4 8.0 8.7 10.4 8.1 8.9 9.6 18.9 30.2 31.0 18.8 28.0 29.2 21.2 27.2 28.2 4.3 5.1 8.5 4.6 5.2 8.4 5.9 6.2 9.0 4.0 3.9 4.1 3.9 4.0 4.1 Climate Scenario 2 3 28.9 28.1 33.7 33.0 34.2 33.5 11.0 10.7 12.7 12.4 18.4 18.0 9.5 9.2 11.1 10.9 16.5 16.2 10.2 10.0 11.2 11.0 16.1 15.8 9.8 9.4 10.8 10.5 12.4 12.1 8.1 7.5 8.8 9.0 10.1 10.1 7.8 7.7 8.1 8.1 9.4 9.3 18.8 18.4 30.1 29.8 30.9 30.7 18.6 18.4 27.9 27.6 29.1 28.9 21.2 20.9 27.0 26.8 28.1 27.9 4.4 4.4 5.2 5.1 8.6 8.4 4.7 4.6 5.2 5.2 8.5 8.3 5.9 5.8 6.2 6.1 9.1 8.8 4.3 4.1 3.9 3.9 4.1 4.1 3.9 3.9 3.9 3.9 4.1 4.1 4 28.5 32.8 33.3 10.5 12.1 17.8 8.9 10.5 16.1 9.9 10.9 15.8 9.3 10.2 11.9 7.7 8.4 9.8 7.6 8.0 9.2 18.4 29.8 30.7 18.5 27.4 28.6 21.4 26.5 27.6 4.3 5.1 8.3 4.6 5.2 8.3 5.9 6.2 8.9 4.2 3.9 4.1 3.9 4.0 4.1 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 5 28.1 32.5 33.0 10.7 12.4 18.1 9.2 10.7 16.4 10.0 11.0 16.0 9.4 10.5 12.2 7.9 8.5 10.0 7.7 8.3 9.4 18.7 29.6 30.3 18.6 27.4 28.4 21.1 26.5 27.4 4.4 5.1 8.6 4.6 5.2 8.5 5.9 6.2 9.1 4.1 3.9 4.1 3.9 3.9 4.1 6 28.2 32.8 33.2 12.1 13.8 19.2 10.7 12.1 17.5 11.1 12.1 16.9 10.5 11.7 13.5 9.0 10.3 11.4 8.9 9.7 10.7 18.3 29.2 30.0 18.2 27.2 28.3 20.8 26.4 27.4 4.4 5.1 8.4 4.6 5.2 8.3 5.8 6.1 8.8 4.4 3.9 4.1 4.0 3.9 4.1 19 Weather Site Ismay, MT Ismay, MT Ismay, MT Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Payson, AZ Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Lake Archetype 25 26 27 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 1 4.1 4.1 4.2 21.5 27.9 28.1 20.3 26.6 27.1 20.5 25.7 26.1 6.1 7.6 13.2 5.7 6.9 12.3 5.8 6.7 11.6 5.6 6.1 7.2 4.8 5.3 6.2 4.4 4.6 5.4 18.9 26.3 26.6 18.1 24.8 25.5 18.3 23.9 24.6 5.3 6.5 10.9 5.4 6.3 10.5 4.1 4.1 4.3 23.4 29.8 30.0 22.1 28.5 29.0 22.1 27.5 28.0 7.6 9.3 15.1 7.1 8.4 14.0 6.9 8.0 13.2 7.1 7.6 9.0 6.2 6.8 7.9 5.6 6.2 7.1 20.7 28.4 28.7 19.8 26.9 27.5 20.0 26.0 26.6 6.6 8.0 12.6 6.5 7.8 12.2 Climate Scenario 2 3 4.1 4.1 4.1 4.1 4.3 4.2 23.3 23.2 30.4 30.0 30.6 30.2 22.1 22.0 29.1 28.8 29.6 29.3 22.2 22.0 28.2 27.9 28.7 28.4 7.6 7.6 9.2 9.0 14.9 14.6 7.0 6.9 8.3 8.3 13.9 13.8 6.7 6.7 7.9 7.9 13.0 13.0 7.0 6.7 7.7 7.4 8.9 8.7 6.0 6.0 6.6 6.6 7.8 7.7 5.4 5.3 5.9 5.9 6.9 7.0 20.7 20.4 28.4 28.0 28.7 28.3 19.9 19.5 26.9 26.5 27.5 27.1 20.0 19.7 26.0 25.5 26.6 26.2 6.6 6.4 7.9 7.8 12.5 12.4 6.4 6.2 7.6 7.5 12.0 12.0 4 5 6 4.2 4.2 4.3 23.0 29.6 29.8 21.8 28.4 28.8 21.8 27.5 27.9 7.4 8.9 14.6 6.8 8.2 13.6 6.7 7.7 12.8 6.9 7.3 8.6 5.8 6.7 7.6 5.4 5.6 6.8 20.1 27.6 27.9 19.3 26.3 26.9 19.3 25.4 26.1 6.3 7.5 12.0 6.3 7.4 11.6 4.1 4.1 4.3 23.3 29.7 29.9 22.0 28.5 28.9 21.9 27.5 28.0 7.6 9.2 15.0 7.0 8.4 14.0 6.7 7.9 13.2 7.0 7.5 8.9 6.1 6.7 7.9 5.4 6.0 7.1 20.4 28.0 28.3 19.6 26.6 27.2 19.7 25.7 26.3 6.5 7.8 12.3 6.3 7.6 12.0 4.1 4.1 4.2 23.2 29.9 30.1 21.9 28.7 29.1 21.9 27.8 28.2 7.9 9.4 15.0 7.2 8.5 14.0 6.8 8.1 13.2 7.3 7.8 9.1 6.5 7.0 8.1 5.7 6.1 7.2 20.6 28.2 28.5 19.8 26.7 27.3 19.9 25.7 26.4 6.6 8.1 12.7 6.5 7.8 12.2 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 20 Weather Site Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Eugene, OR Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Sugarloaf Res., CO Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Lake Archetype 16 17 18 19 20 21 22 23 24 25 26 27 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 1 2 3 4 5 6 0 1 5.4 6.3 10.2 4.4 4.9 6.0 4.4 4.8 5.5 4.4 4.5 5.2 16.6 23.4 23.6 16.5 22.3 22.7 17.6 21.6 22.0 4.3 5.2 8.8 4.5 5.2 8.7 5.4 5.9 9.0 4.0 3.9 4.1 3.9 3.9 4.1 4.0 4.0 4.2 25.4 28.6 28.9 23.9 27.1 27.4 6.5 7.6 11.8 6.1 6.5 7.9 5.5 6.1 7.2 5.6 6.1 7.0 18.0 25.4 25.6 17.9 24.2 24.7 19.0 23.6 24.0 4.4 5.3 9.3 4.6 5.3 9.2 5.6 6.1 9.5 4.1 4.0 4.1 3.9 3.9 4.1 4.0 4.0 4.2 27.0 30.2 30.5 25.6 28.8 29.1 Climate Scenario 2 3 6.3 6.3 7.4 7.3 11.7 11.6 5.8 5.5 6.4 6.2 7.6 7.5 5.4 5.3 6.0 5.8 7.0 6.9 5.5 5.0 5.8 5.8 6.7 6.6 18.1 17.9 25.9 25.4 26.1 25.6 18.0 17.8 24.7 24.4 25.2 24.9 19.2 18.9 24.0 23.8 24.5 24.2 4.4 4.4 5.3 5.3 9.3 9.2 4.6 4.6 5.4 5.3 9.2 9.1 5.6 5.6 6.1 6.0 9.5 9.4 4.0 4.2 3.9 3.9 4.1 4.2 3.9 3.9 4.2 3.9 4.1 4.1 4.0 4.0 4.1 4.0 4.2 4.2 27.5 27.0 31.1 30.4 31.4 30.6 26.2 25.6 29.8 29.0 30.1 29.3 4 5 6 6.1 7.2 11.3 5.5 6.1 7.3 5.4 5.6 6.7 5.2 5.6 6.6 18.1 25.5 25.7 17.9 24.5 24.9 19.0 23.8 24.2 4.4 5.3 9.2 4.6 5.3 9.1 5.5 6.0 9.5 4.0 3.9 4.1 4.1 3.9 4.1 4.0 4.0 4.2 26.6 29.8 30.1 25.2 28.4 28.7 6.3 7.3 11.6 5.5 6.1 7.6 5.4 5.8 7.0 5.5 5.8 6.7 17.9 25.1 25.3 17.8 24.0 24.4 18.7 23.4 23.8 4.5 5.3 9.3 4.6 5.4 9.2 5.6 6.0 9.6 4.2 3.9 4.1 4.0 3.9 4.1 4.1 4.0 4.2 27.2 30.4 30.6 25.7 28.9 29.2 6.5 7.6 11.9 6.1 6.5 7.9 5.5 6.3 7.2 5.4 6.0 6.9 18.0 25.3 25.5 17.8 24.2 24.6 18.9 23.6 24.0 4.4 5.3 9.3 4.6 5.3 9.2 5.5 6.0 9.5 4.1 4.0 4.2 4.1 4.1 4.2 4.0 4.0 4.2 27.1 30.5 30.8 25.7 29.0 29.3 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 21 Weather Site Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Lake Archetype 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 0 23.8 26.3 26.5 14.7 16.1 21.0 14.0 15.3 20.0 13.9 14.9 19.3 13.1 14.2 15.7 12.4 13.3 14.7 12.1 12.8 14.1 1 25.4 28.0 28.3 16.4 17.8 22.7 15.7 17.0 21.7 15.5 16.6 21.0 14.5 15.7 17.4 13.7 14.8 16.3 13.7 14.5 15.7 Climate Scenario 2 3 26.2 25.5 29.1 28.2 29.3 28.4 16.3 16.0 17.7 17.5 22.5 22.3 15.6 15.3 16.8 16.7 21.6 21.4 15.3 15.2 16.4 16.2 20.9 20.7 14.4 14.2 15.6 15.4 17.2 17.0 13.6 13.6 14.6 14.6 16.2 16.1 13.5 13.4 14.2 14.0 15.6 15.4 4 25.0 27.7 27.9 15.9 17.3 22.0 15.3 16.6 21.1 15.0 16.1 20.5 14.1 15.2 16.9 13.5 14.5 15.9 13.2 14.0 15.3 5 25.6 28.2 28.4 16.4 17.7 22.7 15.5 16.9 21.7 15.3 16.5 21.1 14.4 15.6 17.3 13.7 14.8 16.3 13.5 14.2 15.6 6 25.6 28.2 28.5 16.3 17.7 22.5 15.6 17.0 21.6 15.4 16.5 20.9 14.4 15.6 17.3 13.8 14.9 16.4 13.6 14.4 15.7 260 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 22 261 Supplemental Figures 140 OR352709 Average Annual Precipitation (cm) 120 FL088788 NH275780 100 TX412404 80 MN218323 60 AZ026323 CO058064 40 MT244442 CA045114 20 0 0 5 10 15 20 25 Average Annual Temperature ( C) 262 263 264 Figure S-1. Distribution of Average Annual Precipitation and Temperature at Selected Meteorological Stations (b) (a) 0 0 1 2 3 Depth (m) 30 25 20 15 10 5 0 -5 -10 -15 5 6 7 8 9 Depth (m) 1 4 30 25 20 15 10 5 0 -5 -10 2 3 10 11 12 13 Jan Date 265 266 267 Dec 4 Jan Dec Date Figure S-2. Example Water Temperature Contours (°C) for a Lake with Climate of New Durham, NH under Recent Climate Conditions (a) Archetype 14 with Geometry Ratio of 2.8; (b) Archetype 8 with Geometry Ratio of 14.1. Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 23 268 269 Figure S-3. Existing and Projected Mid-21st Century Surface Water Temperatures Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 24 Average Days per Year with Ice Cover 140 Historical Mid-21st C 120 100 80 60 40 20 0 270 271 Figure S-4. Projected Changes in Days per Year with Ice Cover 272 273 274 Figure S-5. Projected Average Annual Energy Exchanges from Atmosphere to Lake across all Sites 275 Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 25 350 20 15 10 Average Days of Ice Cover 25 300 250 200 5 0 1 2 3 4 5 6 7 8 9 10 0 Air Temperature Increase (°C) 120 100 80 60 40 20 0 150 0 a 140 30 Stratification Ratio (days) Integrated Water Temperature (°C) 35 1 2 3 4 5 6 7 8 9 0 10 b 1 2 3 4 5 6 7 8 9 Air Temperature Increase (°C) Air Temperature Increase (°C) c Figure S-6. Lake Response to Enhanced Air Temperature Increases; (a) Depth-Integrated Water Temperature, (b) Stratification Ratio, (c) Average Days of Ice Cover Note: Results shown with 10m wind sheltering. Each colored line represents the average response for a lake with medium depth, medium surface area, and medium water clarity associated with an individual climate station. Panel c displays only sites with significant ice cover under current climate (New Durham, NH, Tracy, MN, Ismay, MT, and Sugarloaf Reservoir, CO). Sensitivity of Lake Thermal and Mixing Dynamics to Climate Change: Supplemental Material 26 10