Gaseous Oxidized Mercury Dry Deposition Measurements in the Southwestern USA: A Comparison between Texas, Eastern Oklahoma, and the Four Corners Area

Table 3

Regression results: coefficients of determination (𝑟²) and sample size (𝑛) for meteorological data modeling for Texas, Oklahoma, and Four Corners area sites.^a

Site	Dry 𝑟^2  (𝑛)	Model dry predictors	Wet 𝑟^2  (𝑛)	Model wet predictors
Corsicana (TX97)	0.12 (24)	TEMP* (+)	na	na
Longview (TX21)	0.14 (26)	WS (+)	0.59 (26)	RAIN*** (+) >> Wind_PP*** (+)
Karnack (TX99)	0.00 (25)	None	na	na
Stilwell, Oklahoma (OK99)	0.06 (78)	R_WNW**𝑝 (+)	0.62 (78)	RAIN*** (+) >> W_SSE*𝑝 (+)
Substation (NM95)	0.64 (44)	TEMP*** (+) >> W_WSW*** (+) > W_NNE (−)	na	na
Mesa Verde National Park (CO99)	0.62 (44)	WS (+) >> TEMP** (+), W_ENE* (−) > R_SSE*𝑝 (−), W_ESE (−), W_SSW (+)	0.43 (46)	RAIN*** (+) >> R_SSE**𝑝 (+), W_NNE** (−)
Valles Caldera National Preserve (NM97)	0.72 (42)	WS*** (+) >> DTEMP** (+) > R_WNW** (+), W_WSW* (+)	0.75 (41)	RAIN*** (+) >> NTEMP*** (+) > R_SSE** (+), R_NNW* (+)
Navajo Lake (NM98)	0.65 (47)	W_ESE (−) >>W_ENE*** (−), TEMP*** (+), WS (+)	0.56 (46)	RAIN*** (+) >> W_ENE*** (+), W_NNW* (+)

aCorsicana (TX97), Karnack (TX99), and Substation (NM95) sites collected GOM dry deposition data only; thus the wet 𝑟² and wet model predictors were not applicable (na). All meteorological variables entered the model at the 0.15 𝑃 level. Asterisks denote more significant 𝑃 levels as *0.10 𝑃-level, **0.05 𝑃-level, and ***0.01 𝑃 level. Model predictors are listed in order of rank based on their contribution to the final model’s explanatory power as indicated by their partial 𝑟² values; >> and > indicate distinctions between the partial 𝑟² of the predictors. The direction of influence on the deposition variable is indicated by a + or − sign. Wind sector predictors are designated as W_XXX or R_XXX to indicate the fraction of time or precipitation, respectively, associated with the XXX sector; a subscript of 𝑝 indicates a power plant sector. The combined power plant sectors are designated as WIND_PP (or RAIN_PP). The other variables are designated as WS for average wind speed; TEMP, DTEMP, or NTEMP for overall, daytime, and nighttime average temperature, respectively; RAIN for total precipitation amount.