-
Salazar 1999.pdf
-
Located in
Resources
/
TRB Library
/
RID-SCH
-
Salazar 2000.pdf
-
Located in
Resources
/
TRB Library
/
RID-SCH
-
Salbenblatt Edgar 1964.pdf
-
Located in
Resources
/
TRB Library
/
RID-SCH
-
Salmon Green 1983.pdf
-
Located in
Resources
/
TRB Library
/
RID-SCH
-
Samad Stanley 1986.pdf
-
Located in
Resources
/
TRB Library
/
RID-SCH
-
Sams, Chuck
-
Located in
Expertise Search
-
Sargent Wright County Minnesota.pdf
-
Located in
Resources
/
TRB Library
/
RID-SCH
-
SARP Aquatic Barrier Prioritization Tool
-
Recently improved inventories of aquatic barriers enable us to describe, understand, and prioritize them for removal, restoration, and mitigation. Through this tool and others, we empower you by providing information on documented barriers and standardized methods by which to prioritize barriers of interest for restoration efforts.
Located in
Resources
/
Products
-
Satellite methods underestimate indirect climate forcing by aerosols
-
Satellite-based estimates of the aerosol indirect effect (AIE) are consistently smaller than the estimates from global aerosol models, and, partly as a result of these differences, the assessment of this climate forcing includes large uncertainties. Satellite estimates typically use the present-day (PD) relationship between observed cloud drop number concentrations (Nc) and aerosol optical depths (AODs) to determine the preindustrial (PI) values of Nc. These values are then used to determine the PD and PI cloud albedos and, thus, the effect of anthropogenic aerosols on top of the atmo- sphere radiative fluxes. Here, we use a model with realistic aerosol and cloud processes to show that empirical relationships for lnðNc Þ versus lnðAODÞ derived from PD results do not represent the atmo- spheric perturbation caused by the addition of anthropogenic aerosols to the preindustrial atmosphere. As a result, the model estimates based on satellite methods of the AIE are between a factor of 3 to more than a factor of 6 smaller than model estimates based on actual PD and PI values for Nc. Using lnðNcÞ versus lnðAIÞ (Aerosol Index, or the optical depth times angstrom exponent) to estimate preindustrial values for Nc provides estimates for Nc and forcing that are closer to the values predicted by the model. Never- theless, the AIE using lnðNcÞ versus lnðAIÞ may be substantially incorrect on a regional basis and may underestimate or overesti- mate the global average forcing by 25 to 35%.
Located in
Resources
/
Climate Science Documents
-
Satellite-based global-ocean mass balance estimates of interannual variability and emerging trends in continental freshwater discharge
-
Freshwater discharge from the continents is a key component of Earth’s water cycle that sustains human life and ecosystem health. Surprisingly, owing to a number of socioeconomic and political obstacles, a comprehensive global river discharge observing system does not yet exist. Here we use 13 years (1994–2006) of satellite precipitation, evaporation, and sea level data in an ocean mass balance to estimate freshwater discharge into the global ocean. Results indicate that global freshwater discharge averaged 36,055 km3∕y for the study period while exhibiting significant interannual variability driven primarily by El Niño Southern Oscillation cycles. The method described here can ultimately be used to estimate long-term global discharge trends as the records of sea level rise and ocean temperature lengthen. For the relatively short 13-year period studied here, global discharge increased by 540 km3 ∕y2 , which was largely attributed to an increase of global- ocean evaporation (768 km3 ∕y2 ). Sustained growth of these flux rates into long-term trends would provide evidence for increasing intensity of the hydrologic cycle.
climate ∣ global water cycle ∣ hydrology ∣ remote sensing ∣ observations
Located in
Resources
/
Climate Science Documents
