As part of the Rain In Cumulus over the Ocean Experiment (RICO) and the Puerto Rico Aerosol and Cloud Study (PRACS), cloud water was collected at East Peak (EP) in Puerto Rico. The main objective of this study was to determine the concentrations of water-soluble species (Cl-, NO3 (-), SO4 (2-), NH4 (+), Ca2+, H+, Mg2+, K+, and Na+) in water samples taken from clouds influenced by tropical trade winds. The most abundant inorganic species were Na+ (average 465 A mu eq l(-1)) and Cl- (434 A mu eq l(-1)), followed by Mg2+ (105 A mu eq l(-1)), SO4 (2-) (61 A mu eq l(-1)), and NO3 (-) (25 A mu eq l(-1)). High concentrations of nss-SO4 (2) (28 A mu eq l(-1)), NO3 (-) (86 A mu eq l(-1)), and H+ (14.5 A mu eq l(-1)) were measured with a shift in air masses origin from the North Atlantic to North American continent, which reflected a strong anthropogenic influence on cloud chemistry at EP. Long-range transport of particles and acid gases seems to be the factor responsible for fluctuations in concentrations and pH of cloud water at East Peak. When under trade wind influences the liquid phase concentrations of all inorganic substances were similar to those found in clouds in other clean maritime environments.
Chemical Composition of Cloud Water in the Puerto Rican Tropical Trade Wind Cumuli
Decesari S;Facchini MC;
2009
Abstract
As part of the Rain In Cumulus over the Ocean Experiment (RICO) and the Puerto Rico Aerosol and Cloud Study (PRACS), cloud water was collected at East Peak (EP) in Puerto Rico. The main objective of this study was to determine the concentrations of water-soluble species (Cl-, NO3 (-), SO4 (2-), NH4 (+), Ca2+, H+, Mg2+, K+, and Na+) in water samples taken from clouds influenced by tropical trade winds. The most abundant inorganic species were Na+ (average 465 A mu eq l(-1)) and Cl- (434 A mu eq l(-1)), followed by Mg2+ (105 A mu eq l(-1)), SO4 (2-) (61 A mu eq l(-1)), and NO3 (-) (25 A mu eq l(-1)). High concentrations of nss-SO4 (2) (28 A mu eq l(-1)), NO3 (-) (86 A mu eq l(-1)), and H+ (14.5 A mu eq l(-1)) were measured with a shift in air masses origin from the North Atlantic to North American continent, which reflected a strong anthropogenic influence on cloud chemistry at EP. Long-range transport of particles and acid gases seems to be the factor responsible for fluctuations in concentrations and pH of cloud water at East Peak. When under trade wind influences the liquid phase concentrations of all inorganic substances were similar to those found in clouds in other clean maritime environments.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
