1. North-South Variations in West Coast Hydrometeorological Parameters 25
• The west coast of South America experiences higher net radiation,
more intensive aridity, and higher sensible heat transfers than does the
west coast of North America in the 14° to 31° latitude band.
• Rivers on the west coast of North America have higher river discharges
in the 45°N to 60°N latitude band than do rivers at comparable
latitudes in South America, due primarily to the larger river-basin
sizes.
• Signficant differences exist in the estimates of runoff, depending on the
methodology used.
Research Needs
The analysis presented here has provided a preliminary consideration of
the effects of hydroclimatic processes on regional biotic patterns. However, this work should be regarded as only preliminary, because a number
of gaps remain to be filled.
Given the sparse observational networks and the highly variable terrain
in this study area, it is essential to develop more reliable models and
techniques for future studies of water and energy budgets on space and
time scales appropriate to understanding and monitoring plant and ecosystem responses. Remote sensing offers many new data sets that could
enable scientists to monitor a wide range of abiotic factors over a number
of time scales on a spatially continuous basis. However, it is necessary to
design studies to develop and validate appropriate techniques for estimating the relevant parameters from remote-sensing data. The relationships between climatic and biological factors , such as the range of species,
cannot be determined with average values alone.
The role of extreme values and the interannual variability arising from
EI Nino events in the biology of this region also need to be studied. When
using localized relationships dealing with links between hydrometeorological metrics and biological indicators developed in different parts of
the world, it is essential to validate them , and it may be necessary to
modify or replace these techniques for the complex geographical region
considered in this study. Factors such as cloud water need to be considered
in studying the water budget of coastal mountain regimes. Many of these
issues can only be addressed by combining field observations with models
and remote-sensing data to account for the extremes in topography that
exist on the west coasts of North and South America.
Acknowledgments. The assistance of Ray Keller in data analysis and in
the preparation of diagrams is greatly appreciated. The comments by the
reviewers have been helpful in describing the limitations of these analyses.
The contributions of Sandra Forsberg in preparing the manuscript are
also appreciated.
• The west coast of South America experiences higher net radiation,
more intensive aridity, and higher sensible heat transfers than does the
west coast of North America in the 14° to 31° latitude band.
• Rivers on the west coast of North America have higher river discharges
in the 45°N to 60°N latitude band than do rivers at comparable
latitudes in South America, due primarily to the larger river-basin
sizes.
• Signficant differences exist in the estimates of runoff, depending on the
methodology used.
Research Needs
The analysis presented here has provided a preliminary consideration of
the effects of hydroclimatic processes on regional biotic patterns. However, this work should be regarded as only preliminary, because a number
of gaps remain to be filled.
Given the sparse observational networks and the highly variable terrain
in this study area, it is essential to develop more reliable models and
techniques for future studies of water and energy budgets on space and
time scales appropriate to understanding and monitoring plant and ecosystem responses. Remote sensing offers many new data sets that could
enable scientists to monitor a wide range of abiotic factors over a number
of time scales on a spatially continuous basis. However, it is necessary to
design studies to develop and validate appropriate techniques for estimating the relevant parameters from remote-sensing data. The relationships between climatic and biological factors , such as the range of species,
cannot be determined with average values alone.
The role of extreme values and the interannual variability arising from
EI Nino events in the biology of this region also need to be studied. When
using localized relationships dealing with links between hydrometeorological metrics and biological indicators developed in different parts of
the world, it is essential to validate them , and it may be necessary to
modify or replace these techniques for the complex geographical region
considered in this study. Factors such as cloud water need to be considered
in studying the water budget of coastal mountain regimes. Many of these
issues can only be addressed by combining field observations with models
and remote-sensing data to account for the extremes in topography that
exist on the west coasts of North and South America.
Acknowledgments. The assistance of Ray Keller in data analysis and in
the preparation of diagrams is greatly appreciated. The comments by the
reviewers have been helpful in describing the limitations of these analyses.
The contributions of Sandra Forsberg in preparing the manuscript are
also appreciated.