dune movement and growth on the Navajo Nation

 dune movement and growth on the Navajo Nation

This article is a review of a journal monitoring and analysis of dune movement and growth on the Navajo Nation, Southwestern United State. The objective of the research was come up with a better understanding of the processes involved in dune growth and their movement, and how the dune mobility and stability are related to climate change. An increasingly dry climate challenges the Native Navajo people. Increased aridity from warmer temperatures, combined with recurring drought, has resulted in a significant amount of migrating sand that affects housing, health, and transportation. More than one-third of Native lands on the Colorado Plateau are covered with sand dunes and sand sheets. Such dunes and sand sheets are standard features of arid and semiarid environments across the globe, where specific conditions of abundant sand supply, the wind, and minimum vegetation cover promote their occurrence.

Growing dune activity, diminished vegetation cover, and an increasingly arid environment. The USGS interdisciplinary studies are focusing on understanding the processes responsible for initiation of Aeolian, sand movement, to including the influence of source sediment availability, climate, vegetation, and land use. Reactivation of inactive dunes could have severe on human and animal populations, agriculture, grazing, and infrastructure on the Navajo Nation and same areas of the Southwest. Annual rainfall in the western Navajo Nation has fallen below 75 mm during the most recent drought. As a result, the areal extent of sand susceptible to mobilization has increased significantly. Moreover, regionally significant sand and dust storms are becoming commonplace during the spring, which is typically dry and windy his justifies the aim of the research.

Several approaches were used to collect data. Monitoring efforts to measure rates of dune movement and growth in active dune fields are achieved by use of different methods. Survey-grade GPS instruments allow the mapping and supervision of dune slip face to within 4 inches (10 cm) while also providing great flexibility in timing data-collection efforts. The ground-based lidar was used to record volumetric changes in two individual dunes within the Grand Falls monitoring site (see map). The lidar instrument collects data at six locations surrounding each dune, recording millions of relative point locations in three dimensions during its scans. These data allow the creation of highly detailed spatial models of the dunes. Repeat scans, before and after the winter/spring windy season, help in understanding the geomorphic changes of the dunes as they move across the landscape

The following Methods were applied during the research. The movement of rises was measured by consolidating surficial mapping with aeronautical and satellite symbolism, GPS, and ground-based lidar estimations. Rates of Hill development and the frequency of going with dust tempests are contrasted with meteorological conditions measured at built up observing destinations. A verifiable review of accessible airborne and satellite symbolism, with resolutions of 3.3 feet (1 m) per pixel or better, has been ordered for the ridge field concentrated on. The assembled symbolism traverses the lifetime of the hill field, from before its appearance in the mid-1950s until 2010.

Estimations of ridge relocation are joined by meteorological checking to comprehend conditions that add to contrasting rates of sand transport and rise development. The Grand Falls observing station is outfitted with a rain gauge, a temperature test, soil dampness test, and anemometers at the upwind and downwind bits of the growing field that quantify wind heading and speed. It additionally has a computerized camera that catches pictures when wind speeds surpass 10 miles for every hour (15 km/hr), giving visual confirmation of dregs development over the surface amid windstorms what’s more, and data on amid dust storms.

This information is being utilized to assess how climate variances contribute to changes fit as a fiddle, size, and relocation rates, and under what conditions dust storms are joined by dust transport. The consequences of this exploration demonstrate that the rate of hill movement in dynamic areas shifts from year to year, contingent upon neighborhood meteorological conditions. In 2009, a strangely blustery and dry year, we quantified hill movement rates as high as 112-157 feet every year contingent upon the territory. With current dry season conditions and commonplace springtime winds, hills in the locale of study can move more than 3.3 feet (1 m) in a solitary windstorm. The general size of dynamic rise fields and the general number of ridges have additionally changed. Appraisal of filed symbolism demonstrates that the Grand Falls field has developed in a real degree by 70 percent from 1992 to 2007, a time of just 15 years. From the research findings, increasing dry climate in the U.S. Southwest has led to accelerated migration of active sand dunes and reactivation of previously inactive dunes. In the Native lands of the Colorado Plateau, sand dunes and sand sheets cover one-third of the area. Migration of these dunes can threaten housing and roads, as at this Navajo settlement.

These studies indicate increasing movement of dunes, which is a cause for concern to local communities. Reactivation of inactive dunes could have serious consequences on human and animal infrastructure on the Navajo Nation and similar areas of the Southwest. Annual rainfall in the western Navajo Nation has fallen below 3 inches (75 mm) during the most recent drought. As a result, the areal extent of sand susceptible to mobilization has increased to detectable levels. Also, regionally significant sand and dust storms are becoming common place during the spring, which is typically dry and windy. The imagery spans the lifetime of the dune field, from before its appearance in the mid-1950s to 2010. In all image, the leading edge of the active dune field was identified, enabling a calculation of the areal extent and migration rates changes for the dune field over the past 60 years.

The research results are correctly presented and clearly explained to make it easy for any individual who access the data. The researcher has used images and maps to show the places with dune and their mobility and stability, and now this is related to climate change. The research explains that an increasingly dry climate currently challenges the native Navajo people of the southwestern United States. The increase in aridity from warmer temperatures, combined with recurring drought, has resulted in the migrating sand that threatens housing, health, and transportation. The data used in the referenced research was not sufficient. The information provided was short and therefore not reliable. The data was not accurately studied because it does not agree with a cause-effect relationship. Also, the sample size is not enough because it is only referring to Navajo area and not any other place. The research was correctly tied to the results found, but still further researches can be done in future.

Work Cited

Bogle, Rian, Margaret Hiza Red steer, and John Vogel. “Field measurement and analysis of climatic factors affecting dune mobility near Grand Falls on the Navajo Nation, southwestern United States.” Geomorphology 228 (2015): 41-51.