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Sequoia National Park Trends Analysis
The tables and figures below show the trends analysis results for 20% worst, middle 60% and 20% best days at SEQU1 based on light extinction coefficient data from 1994 to 2003. No significant trend is found for total aerosol light extinction in 20% worst days. But a significant increase trend in nitrate light extinction coefficients and a significant decrease in soil extinction are found in 20% worst days. A significant decrease in total aerosol light extinction coefficients is found in 20% best days.

Table 1. Number of valid measurements used in the trends analysis
Site Year StartDate EndDate NoMeas
SEQU1 1994 1/1/1994 12/31/1994 100
SEQU1 1995 1/7/1995 12/30/1995 91
SEQU1 1996 1/6/1996 12/28/1996 74
SEQU1 1997 1/1/1997 12/27/1997 97
SEQU1 1998 1/3/1998 12/26/1998 74
SEQU1 1999 1/6/1999 12/29/1999 90
SEQU1 2000 1/1/2000 12/29/2000 107
SEQU1 2001 1/1/2001 12/30/2001 118
SEQU1 2002 1/5/2002 12/31/2002 100
SEQU1 2003 1/3/2003 12/29/2003 89
Table 2. Trends analysis for 20% worst visibility days
Site Year Bep (1/Mm) Sulfate_Ext (1/Mm) Nitrate_Ext (1/Mm) OMC_Ext (1/Mm) LAC_Ext (1/Mm) Soil_Ext (1/Mm) CM_Ext (1/Mm)
SEQU1 1994 122.65 21.73 9.11 25.97 5.30 18.42 42.14
SEQU1 1995 95.56 15.53 10.02 45.83 11.21 1.69 11.28
SEQU1 1996 83.52 13.65 15.68 25.09 9.30 4.45 15.35
SEQU1 1997 88.20 12.89 37.36 21.10 7.63 2.44 6.78
SEQU1 1998 68.74 14.80 25.86 14.42 7.09 1.38 5.19
SEQU1 1999 89.32 15.60 26.98 31.63 8.70 1.09 5.31
SEQU1 2000 121.22 20.55 65.56 19.99 7.52 0.85 6.75
SEQU1 2001 98.91 16.37 50.74 17.10 5.67 0.97 8.07
SEQU1 2002 114.75 14.23 58.05 28.11 7.46 0.92 5.98
SEQU1 2003 113.37 15.35 43.58 33.28 9.72 1.58 9.86
               
Slope (1/Mm/Year)   2.226 -0.022 5.089 -0.440 -0.035 -0.268 -0.756
S-Value   7 -1 31 -3 -3 -27 -13
P-Value   0.300 0.500 0.002 0.431 0.431 0.008 0.146

Table 3. Trends analysis for middle 60% visibility days
Site Year Bep (1/Mm) Sulfate_Ext (1/Mm) Nitrate_Ext (1/Mm) OMC_Ext (1/Mm) LAC_Ext (1/Mm) Soil_Ext (1/Mm) CM_Ext (1/Mm)
SEQU1 1994 52.74 9.71 10.78 15.08 4.85 2.38 9.94
SEQU1 1995 48.46 13.21 9.89 13.61 4.70 1.04 6.02
SEQU1 1996 43.20 8.16 11.90 10.47 4.69 1.16 6.81
SEQU1 1997 45.27 11.18 6.49 14.26 4.96 2.71 5.67
SEQU1 1998 34.89 8.81 7.25 10.84 4.37 0.53 3.09
SEQU1 1999 47.86 12.62 8.95 16.46 4.85 1.01 3.95
SEQU1 2000 51.03 14.18 10.93 14.29 5.25 0.92 5.45
SEQU1 2001 44.03 11.76 9.23 11.43 3.55 1.05 7.01
SEQU1 2002 48.43 12.99 10.37 14.05 3.65 1.19 6.18
SEQU1 2003 49.61 12.11 10.37 15.97 4.30 0.85 6.01
               
Slope (1/Mm/Year)   0.144 0.293 0.025 0.137 -0.077 -0.042 -0.113
S-Value   1 13 3 7 -13 -11 -7
P-Value   0.500 0.146 0.431 0.300 0.146 0.190 0.300

Table 4. Trends analysis for 20% best visibility days
Site Year Bep (1/Mm) Sulfate_Ext (1/Mm) Nitrate_Ext (1/Mm) OMC_Ext (1/Mm) LAC_Ext (1/Mm) Soil_Ext (1/Mm) CM_Ext (1/Mm)
SEQU1 1994 22.98 2.69 11.70 4.22 1.43 0.25 2.69
SEQU1 1995 23.08 2.68 12.42 3.90 1.69 0.17 2.22
SEQU1 1996 16.59 1.72 5.18 3.96 2.13 0.22 3.38
SEQU1 1997 14.68 3.05 2.34 4.75 1.76 0.32 2.46
SEQU1 1998 10.36 1.77 1.11 3.74 1.10 0.13 2.51
SEQU1 1999 18.00 4.52 3.87 5.79 2.01 0.32 1.49
SEQU1 2000 17.72 4.05 4.25 5.20 2.20 0.21 1.81
SEQU1 2001 11.27 2.99 2.85 2.90 1.12 0.12 1.29
SEQU1 2002 14.04 3.69 3.42 3.87 1.35 0.21 1.49
SEQU1 2003 13.08 3.01 2.99 3.95 1.55 0.13 1.46
               
Slope (1/Mm/Year)   -1.071 0.122 -0.439 -0.016 -0.010 -0.007 -0.156
S-Value   -21 13 -17 -5 -1 -15 -27
P-Value   0.036 0.146 0.078 0.364 0.500 0.108 0.008

Page last updated 30 March 2005