The hydrologic cycle results from the combination of energy conversions and atmospheric transport, and the laws of thermodynamics set limits to both. Here, we apply thermodynamics to derive the limits of the strength of hydrologic cycling within the Earth system and about the properties and processes that shape these limits. We set up simple models to derive analytical expressions of the limits...

Hydrologic data collection over scales from centimemrs to continents, from minutes to years is difficult and expensive, so hydrologic models usually conceptualize processes based on simple, often homogeneous, views of nature. This forced oversimplification impedes cientific understanding and management of water resources. As the focus of hydrologic research shifts to larger regional and global ...

Both local and large-scale processes affect the Amazon hydrologic cycle. We investigate the impact of deep soils on the atmosphere through local feedbacks. The Simple Biosphere model, version 3 (SiB3), is coupled to a single column model. Historically, land surface schemes parameterize soil moisture stress based on shallow soils and incorrectly capture seasonal cycles in the Amazon. Following o...

Groundwater, a special hydrological variable and freshwater resource is completely inter-reliant with hydro-metorological, topographic, land use and hydro-geological components of hydrologic cycle. Trend of hydrologic componentsfor future prediction is attempted to confer in this study using Man-Kendall test, linear regression and geometric progression analysis on recorded data collected from r...

In this paper we review the current instrumental evidence regarding climate variations and change during the 20th century emphasizing those changes that are likely to have direct interactions with the biosphere. Three basic questions are addressed: (1) Is the climate getting warmer, (2) is the hydrologic cycle changing, and (3) is the climate becoming more extreme. Based on global near-surface ...

Many of the scientific and societal challenges in understanding and preparing for global environmental change rest upon our ability to understand and predict the water cycle change at large river basin, continent, and global scales. However, current large-scale land models (as a component of Earth System Models, or ESMs) do not yet reflect the best hydrologic process understanding or utilize th...

Using two versions of the GFDL coupled ocean-atmosphere model, one where water vapor anomalies are allowed to affect the longwave radiation calculation and one where they are not, we examine the role of water vapor feedback in internal precipitation variability and greenhouse-gas-forced intensification of the hydrologic cycle. Without external forcing, the experiment with water vapor feedback p...