Influence of coastal morphology on river discharge division and tidal energy transport at tidal junctions in the Kapuas River, Indonesia

Influences of tidal energy advection on the surface energy balance in a mangrove forest

Biogeosciences Discussions ◽

10.5194/bgd-9-11739-2012 ◽

2012 ◽

Vol 9 (8) ◽

pp. 11739-11765 ◽

Cited By ~ 1

Author(s):

J. G. Barr ◽

J. D. Fuentes ◽

M. S. DeLonge ◽

T. L. O'Halloran ◽

D. Barr ◽

...

Keyword(s):

Energy Balance ◽

Surface Energy ◽

Mangrove Forest ◽

Surface Energy Balance ◽

Energy Transport ◽

Tidal Energy ◽

Water Levels ◽

Energy Output ◽

Tidal Flows ◽

The Impact

Abstract. Mangrove forests are ecosystems susceptible to changing water levels and temperatures due to climate change as well as perturbations resulting from tropical storms. Numerical models can be used to project mangrove forest responses to regional and global environmental changes, and the reliability of these models depends on surface energy balance closure. However, for tidal ecosystems, the surface energy balance is complex because the energy transport associated with tidal activity remains poorly understood. This study aimed to quantify impacts of tidal flows on energy dynamics within a mangrove ecosystem. To address the research objective, an intensive study was conducted in a mangrove forest located along the Shark River in the Everglades National Park, FL. Forest-atmosphere energy exchanges were quantified with an eddy covariance system deployed on a flux tower. The lateral energy transport associated with tidal activity was calculated based on a coupled mass and energy balance approach. The mass balance included tidal flows and accumulation of water on the forest floor. The energy balance included temporal changes in enthalpy, resulting from tidal flows and temperature changes in the water column. By serving as a net sink or a source of available energy, tidal flows reduced the impact of high radiational loads on the mangrove forest. Including tidal energy advection in the surface energy balance improved the 30-min daytime energy closure from 73% to 82% over the study period. Also, the cumulative sum of energy output improved from 79% to 91% of energy input during the study period. Results indicated that tidal inundation provides an important mechanism for heat removal and that tidal exchange should be considered in surface energy budgets of coastal ecosystems. Results also demonstrated the importance of including tidal energy advection in mangrove biophysical models that are used for predicting ecosystem response to changing climate and regional freshwater management practices.

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Large-scale scour in response to tidal dominance in estuaries

10.5194/egusphere-egu21-8290 ◽

2021 ◽

Author(s):

Jasper Leuven ◽

Daan van Keulen ◽

Jaap Nienhuis ◽

Alberto Canestrelli ◽

Ton Hoitink

Keyword(s):

Sediment Transport ◽

River Discharge ◽

Large Scale ◽

River Flow ◽

Tidal Flow ◽

Tidal Energy ◽

Local Flow ◽

Flow Acceleration ◽

Flow Through ◽

Tide Interaction

Channel beds in estuaries and deltas often exhibit a local depth maximum at a location close to the coast. There are two known causes of large-scale (i.e. >10 river widths along-channel) channel bed scours: width constriction and draw down during river discharge extremes, both creating a local flow acceleration. Here, we systematically investigate a potential third mechanism. We study the effect of tidal dominance on the equilibrium channel bed in estuaries with a 1D-morphodynamic model. In estuaries, a morphodynamic equibrium is reached when the net (seaward) transport matches the upstream supply along the entire reach. The residual (river) current and river-tide interactions create seaward transport. Herein, river-tide interactions represent the seaward advection of tide-induced suspended sediment by the river flow. Tidal asymmetry typically creates landward transport. The main reason for scour formation is the amplification of tidal flow through funnelling of tidal energy. Only for a scouring profile the drop in river induced current magnitude reduces the river-tide interaction term, so that the net sediment transport matches the upstream sediment transport. When tidal influence is relatively large, and when channel convergence is strong, a equilibrium is only obtained with a scouring profile. We propose a predictor dependent on the width convergence, quantified as SB, and on the ratio between the specific peak tidal discharge at the mouth and the specific river discharge at the landward boundary (qtide/qriver). Scours develop if (qtide/qriver)/SB exceeds 0.3. These results are independent of scale and allow the prediction of scour in estuaries under future changes.

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Summertime influences of tidal energy advection on the surface energy balance in a mangrove forest

Biogeosciences ◽

10.5194/bg-10-501-2013 ◽

2013 ◽

Vol 10 (1) ◽

pp. 501-511 ◽

Cited By ~ 17

Author(s):

J. G. Barr ◽

J. D. Fuentes ◽

M. S. DeLonge ◽

T. L. O'Halloran ◽

D. Barr ◽

...

Keyword(s):

Energy Balance ◽

Surface Energy ◽

Water Column ◽

Mangrove Forest ◽

Surface Energy Balance ◽

Energy Transport ◽

Tidal Energy ◽

Water Levels ◽

Available Energy ◽

Tidal Flows

Abstract. Mangrove forests are ecosystems susceptible to changing water levels and temperatures due to climate change as well as perturbations resulting from tropical storms. Numerical models can be used to project mangrove forest responses to regional and global environmental changes, and the reliability of these models depends on surface energy balance closure. However, for tidal ecosystems, the surface energy balance is complex because the energy transport associated with tidal activity remains poorly understood. This study aimed to quantify impacts of tidal flows on energy dynamics within a mangrove ecosystem. To address the research objective, an intensive 10-day study was conducted in a mangrove forest located along the Shark River in the Everglades National Park, FL, USA. Forest–atmosphere turbulent exchanges of energy were quantified with an eddy covariance system installed on a 30-m-tall flux tower. Energy transport associated with tidal activity was calculated based on a coupled mass and energy balance approach. The mass balance included tidal flows and accumulation of water on the forest floor. The energy balance included temporal changes in enthalpy, resulting from tidal flows and temperature changes in the water column. By serving as a net sink or a source of available energy, flood waters reduced the impact of high radiational loads on the mangrove forest. Also, the regression slope of available energy versus sink terms increased from 0.730 to 0.754 and from 0.798 to 0.857, including total enthalpy change in the water column in the surface energy balance for 30-min periods and daily daytime sums, respectively. Results indicated that tidal inundation provides an important mechanism for heat removal and that tidal exchange should be considered in surface energy budgets of coastal ecosystems. Results also demonstrated the importance of including tidal energy advection in mangrove biophysical models that are used for predicting ecosystem response to changing climate and regional freshwater management practices.

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Energy, transport, and consumption in the Industrial Revolution

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000153 ◽

2019 ◽

Vol 42 ◽

Author(s):

Joseph A. Tainter ◽

Temis G. Taylor

Keyword(s):

Mass Production ◽

Industrial Revolution ◽

Energy Transport ◽

Underlying Assumption

Abstract We question Baumard's underlying assumption that humans have a propensity to innovate. Affordable transportation and energy underpinned the Industrial Revolution, making mass production/consumption possible. Although we cannot accept Baumard's thesis on the Industrial Revolution, it may help explain why complexity and innovation increase rapidly in the context of abundant energy.

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