Arctic Mackenzie Deltachannel planform evolution during 1983–2013 utilisingLandsatdata and hydrological time series

Abstract

Arctic deltas, such as the Mackenzie Delta, are expected to face major climate change and increased human influence in the near future. Deltas are characterised by highly dynamic fluvial processes, and changing climate will cause considerable evolution of the riverine environment.The changes are difficult to predict with existing knowledge and data. This study quantified channel planform change of the Mackenzie Delta , analysing its temporal and spatial patterns. We addressed the main obstacle of research on large remote areas, the lack of data, by developing a unique work flow that utilised Landsat satellite imagery, hydrological time series, remote sensing-based change analysis, and automatic vectorisation of channels. Our results indicate that the Mackenzie Delta experienced constant evolution but at a highly varying rate over the 30 years. The study demonstrates that the magnitude and duration of flood peaks and the presence of spring ice breakup floods determine the rate of Arctic delta planform change.Changing winter conditions and spring flood magnitudes may therefore affect the stability of Arctic deltas. However, no clear trends towards decreased recurrence or magnitude of spring floods or increased instability of the delta plain have yet been observed in the Mackenzie Delta.The delta plain was most dynamic at the beginning and at the end of the examined period, corresponding to intense flooding, whereas the rates of change were subtle during the low-flood period 1994-2007. The largest changes have occurred along the wide Middle Channel and in the outermost delta. Relative to their size, however, smaller meandering channels have been highly dynamic. Hotspots of change in the delta plain are located in anastomosing and braiding channel segments and, at the local scale, in point bars and cut-banks along meandering channels. Our study describes how Landsat satellite data can be utilised for advancing fluvial geomorphological research in remote areas. However, cloudiness in the delta restricts production of dense time series with simultaneous coverage of the whole area and requires manual preprocessing.

Global catchment modelling using World-Wide HYPE (WWH), open data, and stepwise parameter estimation

“…Every year about 30 new persons are trained in HYPE and get access to a piece of the modelled world, resulting in model refinements and various regional assessments around the globe, e.g. climate-change impact on Hudson Bay (Mac-Donald et al, 2018), flow forecasts in the Niger River (Andersson et al, 2017b), hydromorphological evolution of the Mackenzie delta (Vesakoski et al, 2017), and water quality in South Africa (Namugize et al, 2017) or England (Hankin et al, 2019).…”

Seasonal and Morphological Controls on Nitrate Retention in Arctic Deltas

“…Evolving channel network morphology over decadal scales could also shed light on temporal changes in the system but is outside the scope of the study. Although Arctic deltas tend to be more stable than lower latitude deltas due to ice dominance (Overeem et al., 2022), they are yet dynamic systems with planforms that evolve on decadal scales (Vesakoski et al., 2017). The binary masks used in this study provide only a snapshot of the delta network in time.…”

Trends in Satellite Earth Observation for Permafrost Related Analyses—A Review

“…In Canada, most research efforts are concentrated around the Mackenzie Delta and Tuktoyaktuk Coastlands within the Northwest Territories [66,177,183,184,[204][205][206][207][208][209][210][211][212][213][214][215][216][217][218][219] (Figure 5 key region 5). Several more studies are also distributed across the Northwest Territories [58,177,211,[220][221][222][223][224][225][226][227][228][229][230].…”