1. Interpretations: Reading the Book of Earth Case Study 5.2 Unit 5 ҉ Climate of Change InTeGrate Module

3. High-resolution data from the GISP2 ice core, Greenland, and the Byrd ice core, Antarctica, covering the Younger Dryas interval (YD) and adjacent times. Alley R.B. PNAS 97:1331-1334. ©2000 by National Academy of Sciences (a) Byrd ice-isotopic data GISP2 data: (b) Temperature converted from ice- isotopic ratios (c) Accumulation in m ice/year. (d) Methane data (parts per billion by volume) (e) δ 15 N data in per mil (f) Sodium in per mil (g) Calcium in per mil Na and Ca are normalized to their mean concentration in the millennium before the Little Ice Age. The estimate of temperature in the Younger Dryas is plotted as a circle; uncertainties of about ± 3°C are not much larger than the symbol.

4. Methane (ppb) Age (ka) Methane (ppb) Age (ka) Methane (ppb) Age (ka) Methane (ppb) Age (ka) Methane (ppb) Age (ka) Methane (ppb) Age (ka) Methane (ppb) Age (ka) Methane (ppb) Age (ka) Methane (ppb) Age (ka) Methane (ppb) Age (ka) 1871.0000.002627.3786.328526.18811.776674.93714.343397.67726.256491.78338.552593.98545.265596.00958.212459.40374.118493.80793.012 747.7940.133 610.1766.659514.04511.792629.40214.364366.30826.672543.39038.585576.78345.298457.37958.425448.27274.820531.24893.529 745.7700.135 661.7836.816540.35511.805633.44914.411393.62927.653471.54538.619570.71245.313406.78458.664583.86675.482435.11794.051 761.9610.138 651.6646.995494.81911.822655.71114.437464.46227.844465.47438.913581.84345.327466.48658.921480.65375.778469.52294.582 762.9730.140 642.5577.181490.77211.901661.78314.437495.83128.886468.51039.090534.28345.340440.17759.141466.48676.097481.66495.101 738.6870.273 641.5457.510527.20011.932665.83014.458416.90329.549407.79639.291486.72445.397471.54559.370579.81976.739534.28396.140 709.3420.284 628.3907.688486.72411.972629.40214.486400.71229.987466.48639.521550.47445.418494.81959.777516.06977.069519.10596.687 702.2590.294 620.2957.867500.89111.999612.20014.501471.54530.460438.15339.621564.64045.512455.35560.327512.02177.372541.36797.215 712.3780.306 572.7358.233546.42611.999645.59214.516432.08131.326457.37939.832527.20045.550465.47460.778528.21277.686594.99797.745 718.4490.478 664.8188.431531.24812.054619.28314.531531.24832.062476.60540.043521.12945.623459.40361.218520.11778.032590.95098.697 708.3300.565 669.8788.631489.76012.110620.29514.551467.49833.244447.26040.415512.02145.665481.66461.422580.83178.708578.80799.145 708.3300.653 735.6518.828463.45012.146631.42614.603548.45033.452494.81940.800477.61745.703527.20061.696565.65279.040554.52199.610 723.5090.830 660.7719.026497.85512.196628.39014.666435.11733.692505.95040.910496.84345.741544.40261.817597.02179.406572.73599.969 670.8901.007 666.8429.243516.06912.255600.05714.718448.27234.213438.15341.094465.47445.799474.58161.940586.90279.779567.676100.315 690.1161.145 690.1169.451493.80712.396589.93814.820597.02134.737412.85541.590459.40346.195469.52262.092583.86680.156642.557100.614 672.9141.369 718.4499.664502.91412.500495.83114.930589.93835.072463.45041.873455.35546.685530.23662.300598.03380.543647.616100.958 666.8421.481 757.9139.914496.84312.500495.83115.032449.28435.334491.78342.162491.78347.634457.37962.584598.03380.924601.069101.369 658.7471.584 757.91310.153481.66412.647463.45015.138466.48636.112520.11742.305467.49848.047509.99862.874656.72381.326507.974101.794 661.7831.679 711.36610.236604.10412.799487.73615.177539.34336.538479.64142.406487.73648.308437.14163.146646.60481.890584.878102.158 644.5801.779 750.83010.311591.96212.822544.40215.245505.95036.679418.92742.880521.12948.748518.09363.373734.63982.083650.652102.507 662.7951.902 716.42510.399633.44912.912471.54515.367583.86637.041439.16543.207506.96249.132495.83163.564718.44982.868548.450102.939 633.4492.088 709.34210.493711.36612.991481.66415.367577.79537.221479.64143.331533.27149.386462.43863.817673.92583.283452.319103.333 646.6042.193 728.56810.579688.09213.083486.72415.440561.60537.346444.22443.470542.37849.925495.83164.241744.75883.624520.117103.757 644.5802.320 724.52010.672625.35413.151463.45015.684584.87837.470475.59343.607554.52150.461469.52264.873718.44983.956506.962104.184 603.0922.510 740.71110.857682.02113.263491.78315.951560.59337.595436.12943.725554.52150.777518.09365.263511.01084.347476.605104.541 622.3192.615 740.71110.957693.15213.344467.49816.225567.67637.728478.62943.836552.49751.778472.55765.438469.52284.725518.093104.933 672.9142.730 732.61611.061692.14013.421445.23616.507577.79537.868502.91443.958539.34351.778515.05765.691467.49885.495491.783105.264 654.6993.198 749.81811.157683.03313.497455.35516.767566.66437.951483.68844.087561.60552.012453.33166.233446.24885.495492.795105.572 597.0213.310 746.78211.261682.02113.651408.80817.263590.95038.049483.68844.196521.12952.434451.30766.741532.25985.889486.724106.268 624.3423.315 688.09211.369673.92513.783374.40317.477581.84338.091487.73644.296443.21253.080479.64167.037467.49886.293480.653106.624 614.2233.428 689.10411.407655.71113.783364.28417.806566.66438.142492.79544.382498.86753.568493.80767.582454.34386.876457.379106.957 613.2113.804 701.24711.458712.37813.861410.83118.190630.41438.166520.11744.477567.67653.743512.02168.125490.77286.876542.378107.322 616.2474.035 717.43711.505658.74713.921384.52218.587577.79538.192496.84344.580555.53353.988493.80768.413518.09387.439508.986107.708 605.1164.328 745.77011.510647.61614.006360.23618.864592.97338.219494.81944.684544.40255.134458.39168.471499.87987.939563.628108.116 617.2594.484 759.93711.557633.44914.054400.71219.163588.92638.269540.35544.776553.50955.615459.40369.736511.01088.382518.093108.531 605.1164.690 763.98511.589709.34214.069407.79619.751612.20038.298536.30744.876587.91456.305468.51070.519492.79588.861576.783108.655 594.9974.802 778.15111.626632.43814.161398.68920.069601.06938.321517.08144.967579.81956.456472.55770.852540.35589.322501.902108.847 587.9144.965 694.16311.641637.49714.161414.87920.423602.08138.321526.18845.047636.48556.840445.23671.186500.89189.730567.676109.007 596.0095.134 746.78211.652668.86614.228375.41520.731617.25938.349514.04545.110568.68857.147518.09371.824452.31990.134505.950109.175 605.1165.280 745.77011.652639.52114.246417.91522.123583.86638.386543.39045.164486.72457.396462.43872.146449.28490.580 599.0455.387 701.24711.675622.31914.265430.05823.123590.95038.419556.54545.188599.04557.591477.61772.441454.34391.026 593.9855.698 632.43811.703625.35414.284399.70123.298606.12838.452539.34345.206604.10457.794502.91472.747448.27291.487 585.8905.855 598.03311.729643.56814.303418.92724.288556.54538.486560.59345.231609.16457.954453.33172.998435.11791.983 600.0576.260 542.37811.761668.86614.324388.57025.786513.03338.519554.52145.248513.03358.077420.95073.664475.59392.477