Written in EnglishRead online
|Statement||by Paul Andrew Addison|
|Series||Canadian thesis/Thèses canadiennes -- 46422|
|The Physical Object|
|Pagination||119 l. :|
|Number of Pages||119|
Download Studies on evapotranspiration and energy budgets in the high Arctic
The study aimed at investigating the characteristics of the surface energy balance and of the evapotranspiration in a high alpine environment during the vegetation period. At both sites, net. Modelling Evapotranspiration and the Surface Energy Budget in Alpine Catchments 16 Will-be-set-by-IN-TECH soil, different coefﬁcients depending on moisture are requested, together with a functional.
Evapotranspiration and other terms of energy budget, expressed in W/m 2 are shown in Fig. For each month we selected one typical non-cloudy day for which are presented net radiation, sensible and latent fluxes.
Because of the widely open canopy and high wind speed regime, energy storage within the canopy was supposed to be by: Responses of Energy Budget and Evapotranspiration to Climate Change in Eastern Siberia lower active layer thickness in Future is likely to have affected, in some part, the lower ET in.
The Arctic plays a major role in the global circulation, and its water and energy budget is not as well explored as that in other regions of the world.
The aim of this study is to calculate the climatological mean water and energy fluxes depending on the season and on.
The work focused on seasonal variations of energy budget over a 2-year period with emphasis on effects of rainfall, wind speed and radiative budget and irrigation practice on evapotranspiration. This study focused on understanding how variations in geomorphology and vegetation control evapotranspiration (ET) on the Alaskan Arctic tundra coastal plain near Barrow, AK, USA.
ET is the total vapor flux from land to atmosphere, which is the combined flux of direct evaporation, plant transpiration, intercepted precipitation, and sublimation. Studies Arctic Energy Resources and Global Energy Security1 Peter F. Johnston Introduction In recent years the world has become gripped with concerns about climate change and its impact on Arctic ice as well as the perception that increasing global energy consumption might surpass the capacity of energy.
Responses of Energy Budget and Evapotranspiration to Climate Change in Eastern Siberia. By Hotaek Park, Takeshi Yamazaki, and Takeshi Ohta. Submitted: May 19th Reviewed: September 6th Published: March 16th DOI: / Energy budget of Amazonian forests has a large influence on regional and global climate, but relevant data are scarce.
A novel energy partition method based on the maximum entropy production (MEP) theory is applied to simulate evapotranspiration in Amazonia. budgets of the atmosphere and Arctic Ocean. Results are synthesized in section 6. Framework and Study Domains Budget Framework  Following the works of Nakamura and Oort  and Trenberth , consider the energy budget of an atmospheric column, extending from the surface to the top of the atmosphere.
Building on this conceptual. Evapotranspiration (ET) is thereby a central term in the water and energy budget, but also central to ecosystem services like crop production and carbon sequestration.
Evapotranspiration can be estimated using indirect (e.g., abstraction in simplified water budgets) or direct methods (e.g., Eddy correlation or daily energy balance, equation ). It is recommended that indirect methods of estimation be used in most cases, but direct methods should be used when more accurate measurements of evaporation or ET.
The Arctic plays a major role in the global circulation, and its water and energy budget is not as well explored as that in other regions of the world. The aim of this study is to calculate the climatological mean water and energy fluxes depending on the season and on the North Atlantic Oscillation (NAO) through the lower, lateral, and upper.
Evapotranspiration is the key flux within the climate system that couples the water, carbon, and energy cycles (Jung et al., ).
It is estimated that transpiration constitutes 62 ± 12% of total evaporation (Maxwell and Condon, ), thus highlighting the role of vegetation in controlling ET rates.
The rate of evapotranspiration is. Studies of evaporation (E) and evapotranspiration (ET) clearly show that, where soil water is not limiting, the primary variable controlling the rate of E and ET is solar radiation impinging on the evaporating surfaces (irradiance).
Addison, P.A. Studies on evapotranspiration and energy budgets on Truelove Lowland. In: Truelove Lowland, Devon Island, Canada: A High Arctic Ecosystem (ed.
L.C. Energy balance methods are another means for measuring ET based on energy budget methods. Energy balance equation should take into consider all fluxes of energy. The heating and evaporation of water requires energy; therefore, the ET process is limited by the input of energy into the system (i.e.
incoming solar radiation) (Allen et al. Abstract. From theoretical considerations on the surface energy budget, the concepts for thermal inertia mapping of land-surface is derived.
With the aid of an atmospheric radiation transfere model, the physical background for remote sensing of surface temperature is given. The dynamics of evapotranspiration (ET), such as the partitioning to evaporation and transpiration, of polygonal ground on the Arctic Coastal Plain are not well understood.
We assessed ET dynamics, including evaporation and transpiration partitioning, created by microtopographic features associated with high- and low-centered polygons. In this study, we define the High Arctic as a region with an August mean snow area fraction >80% and the Low Arctic as a region with a snow fraction of Arctic was defined as the buffer zone, where the.
Determining the extent to which changes in vegetation assemblages influence evapotranspiration in the Arctic could potentially contribute to a more realistic estimation of evaporation in a warming climate. This project aims to determine whether variations in PET and AET rates measured at six tundra vegetation communities can be attributed to the differing vegetation.
Evapotranspiration is the transfer of energy from the Earth's surface to the atmosphere in the form of latent heat, due to the evaporation of water from the ground and bodies of water, and the transpiration of water from plants.
The transpiration aspect of evapotranspiration accounts for about 10% of the moisture in the atmosphere, with evaporation from oceans and other bodies of water. The drier and warmer conditions that are predicted for most arid, semiarid and subtropical badlands (Fig. A and B) will result in higher and extended periods of soil water deficit may promote regoliths to display a higher density of desiccation cracks, in parallel to thicker regolith layers (Calvo-Cases and Harvey, ).Hence, infiltration capacity after drying periods will.
Earth’s temperature depends on how much sunlight the land, oceans, and atmosphere absorb, and how much heat the planet radiates back to space. This fact sheet describes the net flow of energy through different parts of the Earth system, and explains how the planetary energy budget stays in balance.
Distinctions are made (Figure 4) between reference crop evapotranspiration (ET o), crop evapotranspiration under standard conditions (ET c) and crop evapotranspiration under non-standard conditions (ET c adj).ET o is a climatic parameter expressing the evaporation power of the atmosphere.
ET c refers to the evapotranspiration from excellently managed, large, well-watered fields that. Micrometeorological data required to solve the energy budget by the methods discussed previously were collected at each of the ET sites for a minimum of 1 year, which is considered the minimum period by which seasonal fluctuations in evapotranspiration rates can be evaluated and documented.
spheric energy budget changes as a result of tropical forest removal and how this relates to changes in climatic forcing mechanisms at regional scales.
We have devised a three-dimensional energy accounting method that determines the change in the total atmospheric energy budget and the individual energy budget components for the atmosphere. In oceanic areas of Europe, rainfall is evenly distributed throughout the year, but there is low run off in the summer due to high evaporation.
Thames. In tropical areas, evapotranspiration tends to be high and stable, but a peak in the summer. (Blue Nile) Snowmelt in early spring or summer in mountainaous areas, e.g.
the Great Plains of the USA. Evapotranspiration is a very complex phenomenon, comprising different aspects and processes (hydrological, meteorological, physiological, soil, plant and others).
Farmers, agriculture advisers, extension services, hydrologists, agrometeorologists, water management specialists and many others are facing the problem of evapotranspiration. This book is dedicated to further understanding.
– And lastly vegetation index methods,orinference methods based on the use of remote sensing to compute a reduction factor (such as Kc or Priestley Taylor-alpha parameters) for the estimation of the actual evapotranspira-tion. These approaches consider a potential or reference ET obtained from ground measurements.
The Sahara Desert has high potential evapotranspiration, but receives little rain, and the unused solar energy heats the sand to over degrees Fahrenheit. In the Congo River Basin, there is high potential evapotranspiration and ample precipitation, so less of the potential goes unused.
The result is a much cooler, more humid climate with. evaluated with simulations by HB, and Arctic land surfaces to be evaluated in simulations via a forthcoming paper.  The current modeling study responds to the call for extensive, interdisciplinary, multiscale studies of high north-ern latitude climate through the Study of Environmental Arctic Change (SEARCH) [Overland et al., ].
Evapotranspiration is an important process in the water cycle because it is responsible for 15% of the atmosphere’s water vapor. Without that input of water vapor, clouds couldn’t form and precipitation would never fall.
Evapotranspiration is the combined name for the processes of evaporation and transpiration. The ratio of transpiration to evapotranspiration is influenced by vegetation morphology (Zhou et al., ), climate factors (Granier et al., ), air turbulence (Tuzet et al., ), and soil moisture availability (Shuttleworth and Wallace, ).
Our study associates the T/ET trend with LAI dynamics, climate change, and energy variability. Studies and models of trace-gas flux in the Arctic consider temperature and moisture to be the dominant controls over land–atmosphere exchange1,2, with little attention having been paid to the.
This special case is generally referred to as reference potential evapotranspiration (sometimes seen labeled as ET 0), which can be related statistically to a specific crop type and growth stage of interest (i.e., an 8-foot high corn crop during early grain fill stage) to provide an ideal estimate of crop water needs.
Christine Delire, Jean‐Claude Gérard, A numerical study of the influence of the diurnal cycle on the surface energy and water budgets, Journal of Geophysical Research: Atmospheres, /94JD,D3, (), (). in greater detail than the summary SIR, important components of this study.
These reports are varied in scope and include documentation of basic data, such as spring location and irrigated acreage, and interpretive studies of ground-water flow, geochemistry, recharge, evapotranspiration, and geology. Bello, Richard and K Higuchi, Changing Surface Radiation and Energy Budgets of the Hudson Bay Complex using the North American Regional Reanalysis (NARR) model.
Arctic Science. DOI /AS. Potential evapotranspiration (PET), a basic land climate variable (e.g., Hartmann ), is the rate at which a given climate is trying to evaporate water from the soil–vegetation other words, for given atmospheric and radiative conditions, PET is the surface evapotranspiration (ET) rate that would hold if the soil and vegetation were well watered.A water budget is needed to determine the magnitude of these impacts and to evaluate possible mitigation actions.
DISCUSSION: A water budget describes the various components of the hydrologic cycle. These components are shown in Figure 1. The water budget typically includes: Precipitation (P) Evaporation (E) Evapotranspiration (ET).Potential Evapo Transpiration - quantity of water that could be evaporated plus that which could be transpired by plants with unlimited water (depends on energy) Define AET How much evapotranspiration actually occurs if water is limited (depends on water).