Big COHA logo
           
COHA Overview What's new on COHA COHA tour COHA site map Contact COHA staff
 
   Analysis by state
   Analysis by class I
   Analysis by region
   Descriptive maps
   Backtrajectories
   Trends analysis
   PMF Modeling
   Episode analysis
   Dust analysis
   Tribal analysis
   Fish & Wildlife
   Terms & acronyms
For best results,
please use:
Internet Explorer 5
(or higher)
Netscape 6
(or higher)
more info...
Badlands Wilderness Area Trends Analysis

The tables and figures below show the trends analysis results for 20% worst, middle 60% and 20% best days at BADL1 based on light extinction coefficient data from 1994 to 2003. Overall, there is no significant trend in aerosol light extinction in 20% worst days. But there are statistically significant increases in soil and CM extinctions in 20% worst days. Significant decrease trend is found for aerosol light extinction coefficients in 20% best days, which is caused mainly by decrease in nitrate and OMC light extinction. Sulfate extinction significantly decreased in the middle 60% days.

Table 1. Number of valid measurements used in the trends analysis
Site Year StartDate EndDate NoMeas
BADL1 1994 1/5/1994 12/31/1994 99
BADL1 1995 1/4/1995 12/30/1995 103
BADL1 1996 1/3/1996 12/28/1996 98
BADL1 1997 1/1/1997 12/31/1997 99
BADL1 1998 1/3/1998 12/30/1998 95
BADL1 1999 1/2/1999 12/29/1999 93
BADL1 2000 1/1/2000 12/29/2000 93
BADL1 2001 1/1/2001 12/30/2001 119
BADL1 2002 1/2/2002 12/31/2002 115
BADL1 2003 1/3/2003 12/29/2003 118
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)
BADL1 1994 47.38 22.26 3.38 12.98 2.85 0.80 5.10
BADL1 1995 41.15 22.93 3.57 7.80 2.17 0.70 3.98
BADL1 1996 46.03 25.88 7.44 5.44 2.03 0.58 4.67
BADL1 1997 41.16 21.55 6.13 6.03 1.78 0.61 5.07
BADL1 1998 58.69 27.64 14.52 8.78 2.44 0.71 4.60
BADL1 1999 43.49 19.77 8.41 6.51 2.07 0.85 5.87
BADL1 2000 47.44 18.46 3.92 13.80 3.81 1.04 6.42
BADL1 2001 49.09 24.18 7.10 7.65 2.52 1.34 6.29
BADL1 2002 42.00 19.52 5.34 6.94 1.96 1.14 7.11
BADL1 2003 47.77 17.57 7.86 12.16 2.80 0.71 6.67
               
Slope (1/Mm/Year)   0.168 -0.550 0.254 0.182 0.026 0.048 0.336
S-Value   11 -19 13 5 3 21 29
P-Value   0.190 0.054 0.146 0.364 0.431 0.036 0.005

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)
BADL1 1994 25.91 12.22 3.59 5.00 1.37 0.50 3.23
BADL1 1995 22.07 10.40 3.57 4.00 1.39 0.40 2.31
BADL1 1996 24.41 12.07 2.42 4.36 1.41 0.47 3.70
BADL1 1997 21.65 11.10 1.83 3.82 1.13 0.41 3.36
BADL1 1998 26.11 12.99 2.94 5.35 1.64 0.50 2.70
BADL1 1999 20.22 8.77 1.63 4.48 1.35 0.57 3.41
BADL1 2000 22.68 9.86 2.96 5.14 1.74 0.56 2.42
BADL1 2001 24.01 10.64 3.73 4.08 1.50 0.73 3.32
BADL1 2002 20.64 8.59 2.94 3.82 1.12 0.66 3.50
BADL1 2003 21.12 8.73 3.40 4.15 1.29 0.49 3.06
               
Slope (1/Mm/Year)   -0.433 -0.388 0.002 -0.056 -0.005 0.027 0.021
S-Value   -15 -23 1 -7 -3 19 3
P-Value   0.108 0.023 0.500 0.300 0.431 0.054 0.431

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)
BADL1 1994 14.56 4.84 3.68 2.42 1.13 0.37 2.13
BADL1 1995 11.96 3.79 3.60 2.10 0.74 0.24 1.48
BADL1 1996 13.09 5.70 1.77 2.70 0.87 0.25 1.80
BADL1 1997 10.22 4.06 0.77 2.39 0.70 0.24 2.05
BADL1 1998 11.24 4.40 1.17 2.40 0.85 0.32 2.11
BADL1 1999 10.09 4.20 1.24 1.89 0.89 0.30 1.57
BADL1 2000 10.89 4.98 1.50 1.98 0.88 0.26 1.29
BADL1 2001 11.13 4.45 1.81 1.95 0.95 0.40 1.57
BADL1 2002 9.46 3.07 1.00 2.00 0.93 0.44 2.02
BADL1 2003 8.61 3.56 0.87 1.91 0.70 0.24 1.33
               
Slope (1/Mm/Year)   -0.490 -0.128 -0.178 -0.056 0.003 0.003 -0.039
S-Value   -31 -11 -19 -23 1 5 -15
P-Value   0.002 0.190 0.054 0.023 0.500 0.364 0.108

Page last updated 4 May 2005