Property:Theory movie
From CSDMS
This is a property of type Text.
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In Arctic landscapes, recent warming has significantly altered geomorphic process rates. Along the Beaufort Sea coastline bounding Alaska’s North Slope, the mean annual coastal erosion rate has doubled from ~7 m/yr for 1955-1979 to ~14 m/yr for 2002-2007 (Mars and Houseknecht, 2007). Locally the erosion rate can reach 30 m/yr. We aim to understanding the processes that influence coastal erosion rates; since we want to predict the response of the coast and its adjacent landscape to a rapidly changing climate, with implications for sediment and carbon fluxes, oilfield infrastructure, and animal habitat.
The evolution of the permafrost bluffs on the North Slope is controlled by three conditions: length of the sea ice free season, warming sea water and wave and storm surge. During the sea ice-free season, relatively warm waters melt a notch into the ice-rich silt that comprises the 4-m tall bluffs. The bluffs ultimately fail by toppling of polygonal blocks bounded by mechanically weak ice-wedges that are spaced roughly 10-20 m apart. The toppled blocks then temporarily armor the coast against further attack.
The annual coastal retreat rate is controlled by the length of the sea ice-free season, water and air temperatures, and the wave history. Honoring the high ice content of the bluff materials, it is thought that subaerial melt plays a minor role, and that the notching of the base of the bluff acts as an melting dirty ice berg. In quantitative iceberg melting models the local instantaneous melt rate goes as the product of the temperature difference between seawater and bluff material, and the wave height. Calculated instantaneous melt rate can be adjusted to account for the ambient temperature of the permafrost and the presence of non-ice material in the bluffs. Once a block is sufficiently undercut to become unstable it will fail and topple. The latter process can be described as a torque balance. +
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Large and small dam emplacement in the USA. Data shown from the National Inventory of Dams (NID). +
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Liquid water is thought to move through the Greenland Ice Sheet as diffuse and channelized flow, and is governed by the pressure field created by the weight of overlying ice. This 2-D model combines the governing equations for both types of flow to model the movement of water in the Greenland Ice Sheet.
A video of the talk Mauro Werder gave at the CSDMS 2013 annual meeting is available on the CSDMS website,
https://csdms.colorado.edu/wiki/CSDMS_2013_annual_meeting_Mauro_Werder +
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Liquid water is thought to move through alpine glaciers as diffuse and channelized flow, and is governed by the pressure field created by the weight of overlying ice. This 2-D model combines the governing equations for both types of flow to model the movement of water in the the Gornergletscher, an alpine glacier in Switzerland.
A video of the talk Mauro Werder gave at the CSDMS 2013 annual meeting on glacial hydrology is available on the CSDMS website, https://csdms.colorado.edu/wiki/CSDMS_2013_annual_meeting_Mauro_Werder +
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Meandering rivers are ubiquitous in nature, but have been difficult to simulate in flumes.
The snake-like pattern found in meandering rivers occurs as meanders migrate as the outer bank of a river erodes sediment, and the inner curve of a river receives deposits of sediment. +
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Movement of sea ice unto a structure is called ice encroachment. This occurs in two dfferent modes: 'ride up' and 'pile-up'. Ride-up occurs when the ice is driven up the side slope intact, pile-up ocurs when the ice fails and buckles and bends into individual blocks.
It has been assumed that pile up would be more prevalent in shallow water, due to grounding of the ice and due to the fact that a river is very closeby. The river discharge starts draining unto the sea ice by May-June and makes the sea ice more weak and vulnerable for break-up. +
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Reference: Lehner, B., C. Reidy Liermann, C. Revenga, C. Vörösmarty, B. Fekete, P. Crouzet, P. Döll, M. Endejan, K. Frenken, J. Magome, C. Nilsson, J.C. Robertson, R. Rodel, N. Sindorf, and D. Wisser. 2011. High-Resolution Mapping of the World's Reservoirs and Dams for Sustainable River-Flow Management. Frontiers in Ecology and the Environment 9:494-502. DOI: 10.1890/100125. +
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Relating nested models of different oceanographic and climate events to model large-scale processes. +
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Rivers channels can develop a sinuous course through their valleys and lowlands. River with channels with high sinuosity are called meandering rivers. These systems develop over time, by outward migration of the cutbank and simultaneous growth of the pointbar. +
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Sea ice has retreated far into the Arctic Ocean in the last few years, with 2007 being record low over the last 30 years. The animations shows the evolution of sea ice through winter-spring-summer and fall for 2009, which was the secondmost low year. +
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See the topoflow model in the repository. +
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Shows the effects of reworking of different chronologically deposited sedimentary layers due to wave processes. +
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The Mississippi River floods in April and May 2011 are among the largest and most damaging along U.S. rivers in the past century, rivaling major floods in 1927 and 1993. The river water stage points to exceedance of the 500-year flood recurrence interval. Flood waters were derived from two storm systems associated with devastating tornadoes, which dumped record rainfall on the Mississippi River watershed in April 2011
In addition, snowmelt added to the high water levels and by the beginning of May the water stages were record-high. Areas along the Mississippi experiencing flooding include the states of Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana.
On May 3 and 4th, 2011 the US Army Corps of Engineers blasted breaches into the levee protecting the Bird's Point-New Madrid floodway, flooding 530 km2 of crops and farmland in Mississippi County, Missouri. The breach was induced to save Cairo, IL (population ~3000) at the confluence of the Ohio and Mississippi River and the rest of the levee system, from floodwaters. The breach displaced around 200 residents of Missouri's Mississippi and New Madrid counties, at the same time the city of Cairo was evacuated for safety, but remained unharmed.
Birds Point is part of the New Madrid Floodway Project. Prompted by the Great Flood of 1927 the US Army Corps of Engineers installed an earthen levee to protect nearby farmland. The section of the Levee at Birds Point was engineered so that when the water reached 61 feet (19 m) on the nearby Cairo flood gauge, the river would over-top the levee and erode it away. This would allow the river to fill the 133,000 acres (54,000 ha) floodway and relieve pressure on the levees.systems in place at nearby Cairo and Hickman, Kentucky. This area has been engineered to allow intentional flooding but has only been used twice (1937 and 2011).
The levee at Birds Point locally has a "fuse-plug design”; it contains 3,400 m of pipe that can be filled with liquid explosives and detonated to open the levee and activate the floodway. It was only the second time the floodway was ever activated on May 2, 2011, the earlier time being 1937. Three detonations took place in the late evening of May 2, and the following detonations on May 3.
The Mississippi River floods in May 2011 are among the largest and most damaging US floods in the past century, rivaling major floods in 1927 and 1993. The river water stage recorded point to exceedance of the 500-year flood recurrence interval. Flood waters were derived from two storm systems associated with devastating tornadoes, which dumped record rainfall on the Mississippi River watershed in April 2011.
In addition, snowmelt added to the high water levels and by the beginning of May the water stages were record-high. Areas along the Mississippi experiencing flooding include the states of Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana.
On May 3, 2011 the US Army Corps of Engineers blasted a breach into the levee protecting the Bird's Point-New Madrid floodway, flooding 530 km2 of crops and farmland in Mississippi County, Missouri. The breach was induced to save Cairo, IL (population ~3000) at the confluence of the Ohio and Mississippi River and the rest of the levee system, from floodwaters. The breach displaced around 200 residents of Missouri's Mississippi and New Madrid counties, at the same time the city of Cairo was evacuated for safety, but remained unharmed.
Birds Point is part of the New Madrid Floodway Project. Prompted by the Great Flood of 1927 the US Army Corps of Engineers installed an earthen levee to protect nearby farmland. The section of the Levee at Birds Point was engineered so that when the water reached 61 feet (19 m) on the nearby Cairo flood gauge, the river would over-top the levee and erode it away. This would allow the river to fill the 133,000 acres (54,000 ha) floodway and relieve pressure on the flood control systems in place at nearby Cairo, Illinois and Hickman, Kentucky. This whole area has been engineered to allow for intentional flooding but has only been used twice.
The levee at Birds Point locally has a "fuse-plug design”; it contains 3,400 m of pipe that can be filled with liquid explosives and detonated to open the levee and activate the floodway. It was only the second time the floodway was ever activated on May 2, 2011, the earlier time being 1937. Three detonations took place in the late evening of May 2, and the following detonations on May 3.
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The flow of water in rivers over loose sediments can lead to self organizing patterns, such as the ripples presented in this simulation.
Generally, as the strength of the flow of water increases, low-flow bed forms evolve from a flat surface, to ripples, and then dunes. As higher flows occur, anti-dunes and eventually pools and chutes form.
For more information see the related papers:
doi: 10.1002/wrcr.20457
doi: 10.1002/wrcr.20303
doi: 10.1029/2012WR011911 +
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The importance of the coastal zone as a zone of resources; ecosystem services, hydrocarbons, recreation is illustrated. +
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This is part of a study examining the evolution of a transition region between the arid and Mediterranean climates in Israel. The main soil production process in this region is Aeolian deposition of Loess type soils. The Loess accumulation has persisted throughout the late-Pleistocene and early Holocene, peeked about 18 kyr BP and ceased about 9 kyr PB.
The hillslopes in this region are now mostly depleted of soil cover with some loess patches at the foothills and deep loess deposits at the valleys (see figures). We set to examine the mechanisms and drivers (climatic and/or anthropogenic) that led to this landscape.
In this animation we used the mARM4D soil-landscape model to compare the sediment transport mechanisms on one small ridge. The three synchronized 80 kyr animations are for when (1) only fluvial transport is simulated (top-left), (2) only diffusive transport is simulated (top-right) and (3) when both are simulated (bottom-right). The plot on the bottom-left of the movie shows the temporal changes in the processes parameters (based on literature analysis) representing climatic and anthropogenic effects. +
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This landslide is a typical example of a deep-seated landslide. These are landslides in which the sliding surface is below the maximum rooting depth of trees (typically to depths greater than ten meters).
The video shows a scar in the hillslope of several 10's of meters high. It can also be seen that there is a very deep weathered soil (or regolith).
These events typically move slowly, only several meters per year, but occasionally move faster. This is what happened in this event, the slide already showed slow movement before speeding up. The people living in the town of Maierato were evacuated in time.
Whereas the video show the fresh scar, such hillslope scars can be mapped by concave scarps at the top and steep areas at the toe for many years after. +
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This movie just indicates the emplacements of larger reservoirs over time and gives an idea of how humans are impacting and controlling the hydrological cycle +
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This movie loops through sea ice concentration in the Chukchi and Beaufort Sea. Sea ice concentration (SSC) is measured by satellites on a daily basis. SSC has been measured from 1979 onwards, and thus provides us with a relatively long time-series to assess changes in the Arctic climate.
The animation loops through the year 2007, which was a relatively warm year with a low sea ice minimum.
The presence of sea ice impacts the time that waves and storm surge can affect the coast. Another parameter that affects waves and storm surge is the fetch-the distance that wind blows over open water. Here we show how we calculate each day the distance to the sea ice edge over all relevant directions (the grey lines). Then we pick the the average wind direction measured at the Barrow airfield for that day, and determine the fetch length in that specific direction (the red line). +
