Chapter 1. A. J. W. Catchpole: Hudson's Bay Company Ships' Log-Books as Sources of Sea Ice Data, 1751-1870. 1. ANNUAL INDICES OF SUMMER SEA ICE SEVERITY. These indices are used in the construction of Figure 2.7 and in the compilation of Tables 2.1 and 2.2. The three records refer to Hudson Strait, Eastern Hudson Bay and Western Hudson Bay. The method used to derive the Hudson Strait indices (Catchpole and Faurer, 1983) is different from that used to derive the two sets of indices in Hudson Bay (Catchpole and Halpin, 1987; Catchpole and Hanuta, 1989). Table 1. Annual Indices of Summer Sea Ice Severity in Hudson Strait Year 0 1 2 3 4 5 6 7 8 9 1750 * 6 7 16 32 24 4 9 40 10 1760 21 13 20 17 14 34 11 23 8 9 1770 15 20 13 14 16 9 18 14 21 21 1780 21 13 7 35 19 12 10 16 9 19 1790 17 25 14 12 10 10 8 12 23 23 1800 21 16 13 11 12 12 12 15 8 23 1810 12 21 21 16 29 18 44 23 19 17 1820 6 18 9 15 23 15 9 13 16 8 1830 5 13 21 13 12 8 31 27 30 * 1840 * * 17 8 16 5 9 24 11 8 1850 11 11 10 10 29 16 11 9 10 27 1860 7 13 23 18 11 22 12 9 10 8 1870 16 7 13 13 11 40 8 9 7 11 1880 15 8 11 33 36 25 16 26 12 24 Notes: (1) The record from 1751 to 1871 was reconstructed using the method given in Catchpole and Faurer (1983). The indices for 1872 to 1889 were estimated using a procedure outlined in Catchpole and Hanuta (1989). (2) Asterisks indicate gaps in the log-book record. Table 2. Annual Indices of Summer Ice Severity in Western Hudson Bay. Year 0 1 2 3 4 5 6 7 8 9 1750 * -4 6 0 0 0 26 0 10 88 1760 16 0 27 127 13 20 -5 8 9 3 1770 25 15 16 10 7 44 12 -1 3 174 1780 0 -4 4 0 4 40 3 -4 2 20 1790 0 0 15 2 0 64 35 61 20 0 1800 0 0 86 20 4 -9 0 0 84 0 1810 19 * 19 0 0 105 0 * 13 0 1820 38 65 2 22 5 10 0 83 15 -8 1830 38 * -2 0 0 83 399 11 8 * 1840 * * -3 21 30 43 9 0 15 13 1850 5 * 12 0 5 207 0 7 5 4 1860 0 0 4 2 0 0 147 -4 3 3 Table 3. Annual Indices of Summer Ice Severity in Eastern Hudson Bay. Year 0 1 2 3 4 5 6 7 8 9 1750 * -17 -2 -2 -12 -4 8 1 63 80 1760 0 4 -6 0 -5 -3 19 33 2 0 1770 * 21 * * 74 * * 126 -12 * 1780 -6 -20 3 0 2 124 0 17 41 * 1790 -12 -6 12 56 -10 -20 31 11 -15 -6 1800 -6 5 7 30 -5 -13 -10 4 2 -9 1810 8 0 23 180 -3 4 113 108 -8 -8 1820 -4 22 -1 2 43 1 0 -1 36 94 1830 122 -6 * -1 -6 -2 12 16 -6 * 1840 * * 34 288 85 150 -7 -2 9 -8 1850 0 46 0 0 -6 2 0 -1 -3 24 1860 2 -10 -4 -2 * 85 68 1 9 85 1870 0 2. THERMAL INDICES FOR SOUTHEAST COAST OF HUDSON BAY These indices are used in the construction of Figure 2.7. They comprise estimates of departures from 1941 to 1970 normals of the May to June temperatures in each year during the nineteenth century. The data presented here in Table 4 are taken directly from Table B-4a in Wilson (1988). Table 4. Reconstructed Spring Temperature Anomalies øC, May/June, east coast Hudson/James Bay. Year 0 1 2 3 4 5 6 7 8 9 1800 0.0 +1.5 -0.5 -1.0 +3.0 +1.0 -0.5 -2.0 -0.5 -1.0 1810 0.0 +1.5 -4.5 +1.5 -1.0 -4.0 -3.5 -6.5 +1.0 -2.0 1820 -0.5 -2.5 * -3.5 -4.0 0.0 -0.5 +0.5 0.0 -1.5 1830 -3.5 -1.5 * -0.5 -1.0 -2.5 -2.5 -3.5 -4.0 -2.0 1840 -1.0 0.0 -4.0 -3.5 -2.0 -3.0 +0.5 -1.5 -2.5 -3.5 1850 +0.5 0.0 -3.0 -3.5 0.0 * * -1.0 +0.5 * 1860 * * -3.0 +0.5 -1.0 -3.0 -2.5 +0.5 +1.5 -1.5 1870 +3.0 -2.5 0.0 +3.0 -1.0 0.0 -0.5 +1.5 +3.0 -1.5 1880 +0.5 +1.0 -1.0 -0.5 -1.0 -1.5 -1.5 +0.5 +1.0 -0.5 1890 -1.0 -2.0 0.0 +2.0 +0.5 -0.5 +0.5 -1.5 -1.0 -1.0 1900 -2.0 * * * * * * * * * *anomaly not reconstructed References: Catchpole, A.J.W. & M.A. Faurer 1983. Summer sea ice severity in Hudson Strait, 1751-1870. Climatic Change 5, 115-39. Catchpole, A.J.W. & J. Halpin 1987. Measuring summer sea ice severity in eastern Hudson Bay, 1751-1870. The Canadian Geographer 31, 233-44. Catchpole, A.J.W. & I. Hanuta 1989. Severe summer ice in Hudson Strait and Hudson Bay following major volcanic eruptions, 1751 to 1889 A.D. Climatic Change 14, 61-79. Wilson, C.V. 1988. The summer season along the east coast of Hudson Bay during the nineteenth century: Part III summer thermal and wetness indices, B. The indices 1800 to 1900. Report 88-3. Downsview, Ontario: Canadian Climate Centre, Atmospheric Environment Service.