Heterogeneous Changes in Western North American Glaciers Linked to Decadal Variability in Zonal Wind Strength

Menounos, Brian; Hugonnet, Romain; Shean, David; Gardner, Alex; Howat, I. M.; Berthier, Étienne; Pelto, Ben M.; Tennant, C.; Shea, J. M.; Noh, Myoung-Jong; Brun, Fanny; Dehecq, Amaury

doi:10.1029/2018gl080942

Cited by 80 publications

(88 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The strongest negative correlation is between ONI and SD DUR (−0.81 ± 0.46, p < 0.001). We conclude that, similar to previous studies (e.g., Fleming and Whitfield, 2010;Moore and McKendry, 1996;Whitfield et al, 2010), El Niño (La Niña) events and positive (negative) PDO events result in earlier (later) melt and shorter (longer) snow duration in BC. When we compare seasonal ONI and PDO values to provincial snow measurements (SD ON , SD OFF , and SD DUR ), we see seasonal variation in the response (Fig.…”

Section: Snow Season Resultssupporting

confidence: 90%

“…Hemispheric-scale circulation patterns, or ocean-atmosphere teleconnections, are known to influence the climatology of western Canada; the most influential patterns include the PDO (Stahl et al, 2006a;Whitfield et al, 2010), ENSO (Moore and McKendry, 1996;Shabbar, 2006), Pacific North American pattern (PNA; Bonsal and Shabbar, 2008;Stahl et al, 2006a), and Arctic Oscillation (AO; Burn, 2008;Fleming et al, 2016). Anthropogenic climate change is also an important influence on snow cover in BC (e.g., White et al, 2016;Foord, 2016;Islam et al, 2017;Najafi et al, 2017;Schnorbus et al, 2014); however, climate change studies require long time series and are complex due to the potential influence of climate change on the ocean-atmosphere teleconnections themselves (e.g., Cai et al, 2018).…”

Section: Ocean-atmosphere Teleconnections and The Snowpack Of Britishmentioning

confidence: 99%

“…1). Generally mild and dry winters in BC have been identified as important factors in forest insect outbreaks (Stahl et al, 2006b), wildfire activity (Crowley et al, 2019), glacier change (e.g., Menounos et al, 2018), and overall drought conditions (Trishchenko et al, 2016). The winter snowpack differs in timing and duration throughout the province and is influenced by, among other processes, climate change (e.g., Allchin and Déry, 2017;Foord, 2016;Najafi et al, 2017), local geography (e.g., Moore and McKendry, 1996;Schnorbus et al, 2014;Stahl et al, 2006a), land cover change (e.g., Boon, 2012), and ocean-atmosphere teleconnections (e.g., Fleming and Whitfield, 2010;Hsieh and Tang, 2001;Shabbar, 2006;Winkler and Moore, 2006).…”

Section: Introductionmentioning

confidence: 99%

“…The El Niño-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) have been identified as the two most influential ocean-atmosphere teleconnections on snow cover in BC (Moore and McKendry, 1996). This paper investigates the regional effects of ENSO and PDO on the MODIS-derived SD ON and SD OFF and the total duration of snow cover (SD DUR ) in BC.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Regional influence of ocean–atmosphere teleconnections on the timing and duration of MODIS-derived snow cover in British Columbia, Canada

et al. 2019

View full text Add to dashboard Cite

We use the twice-daily Moderate Resolution Imaging Spectroradiometer (MODIS) snow cover product to study the regional influence of the Oceanic Niño Index (ONI) and Pacific Decadal Oscillation (PDO) on snow cover in British Columbia (BC). We apply a locally weighted regression (LOWESS) interpolation to the MODIS normalized difference snow index (NDSI) time series to detect the timing and duration of snow. We confirm the general consensus from many previous in situ studies that both ONI and PDO have significant impacts on snow cover in BC. We add to this knowledge by performing seasonal and regional analysis using established hydrozones and explore variation in our results by elevation bins of 500 m. We calibrated our method with in situ snow water equivalent (SWE) data and found an optimal NDSI threshold of 30 for detecting continuous snow cover. We separate automatic snow weather station data into calibration (75 %) and validation (25 %) subsets and obtain mean absolute errors between the MODIS and in situ observations for the start, end, and duration of 8.7, 8.9, and 13.1 d for the calibration data and 12.7, 12.6, and 16.6 d for the validation data, respectively. In general, the start date of snow is poorly correlated with both ONI and PDO, whereas the end date and duration are strongly negatively correlated. Regional patterns emerge wherein northern and southern BC are most correlated with the PDO and the ONI, respectively. These relationships are generally stronger at lower elevations and vary spatially. This study demonstrates that the suitability of ocean-atmosphere teleconnections as predictors of the timing and duration of snow varies throughout BC.

show abstract

Section: Snow Season Resultssupporting

confidence: 90%

Section: Ocean-atmosphere Teleconnections and The Snowpack Of Britishmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Regional influence of ocean–atmosphere teleconnections on the timing and duration of MODIS-derived snow cover in British Columbia, Canada

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The total rock mass lost at the source is 5.2 × 10 6 m 3 , and the accumulated material in the deposit is 4.9 × 10 6 m 3 with respective uncertainties of ± 2.01% and ± 13.65%. The source and deposit uncertainties reflect the standard deviation (± 1σ) of stable terrain following methods described elsewhere (Menounos et al 2019). While there is good agreement between the total source volume estimates from the photogrammetry and Lidar analyses, the deposit volume is smaller than expected considering that bulking and dilation would have occurred.…”

Section: Volume Estimatesmentioning

confidence: 95%

Observations on the May 2019 Joffre Peak landslides, British Columbia

et al. 2020

View full text Add to dashboard Cite

Two catastrophic landslides occurred in quick succession on 13 and 16 May 2019, from the north face of Joffre Peak, Cerise Creek, southern Coast Mountains, British Columbia. With headscarps at 2560 m and 2690 m elevation, both began as rock avalanches, rapidly transforming into debris flows along middle Cerise Creek, and finally into debris floods affecting the fan. Beyond the fan margin, a flood surge on Cayoosh Creek reached bankfull and attenuated rapidly downstream; only fine sediment reached Duffey Lake. The toe of the main debris flow deposit reached 4 km from the headscarp, with a travel angle of 0.28, while the debris flood phase reached the fan margin 5.9 km downstream, with a travel angle of 0.22. Photogrammetry indicates the source volume of each event is 2-3 Mm 3 , with combined volume of 5 Mm 3 . Lidar differencing, used to assess deposit volume, yielded a similar total result, although error in the depth estimate introduced large volume error masking the expected increase due to dilation and entrainment. The average velocity of the rock avalanche-debris flow phases, from seismic analysis, was~25-30 m/s, and the velocity of the 16 May debris flood on the upper fan, from superelevation and boulder sizes, was 5-10 m/s. The volume of debris deposited on the fan was~10 4 m 3 , 2 orders of magnitude less than the avalanche/debris flow phases. Progressive glacier retreat and permafrost degradation were likely the conditioning factors; precursor rockfall activity was noted at least~6 months previous; thus, the mountain was primed to fail. The 13 May landslide was apparently triggered by rapid snowmelt, with debuttressing triggering the 16 May event.

show abstract

Spatial and temporal controls on proglacial erosion rates: A comparison of four basins on Mount Rainier, 1960 to 2017

Anderson

Shean

2021

Earth Surf Processes Landf

Self Cite

View full text Add to dashboard Cite

The retreat of alpine glaciers since the mid-19th century has triggered rapid landscape adjustments in many headwater basins. However, the degree to which decadal-scale glacier retreat is associated with systematic or substantial changes in overall coarse sediment export, with the potential to impact downstream river dynamics, remains poorly understood. Here, we use repeat topographic surveys to assess geomorphic change in four partly glaciated basins on a stratovolcano (Mount Rainier) in Washington State at roughly decadal intervals from 1960 to 2017. The proglacial extents of the four basins show distinct geomorphic trajectories, ranging from substantial and sustained net erosion to relatively inactive with net deposition.These different trajectories correspond to differences in initial (1960) valley floor gradients, and can be effectively understood as valley floor grade adjustments. Significant erosion was most often accomplished by debris flows triggered by extreme rainfall or glacial outburst floods, though a single rockfall mobilized more material than all other events combined. Year-to-year runoff events had little measurable geomorphic impact. Exported material tended to accumulate in broad deposits within several kilometers of source areas and largely remained there through the end of the study period. Over 10-to 100-year timescales, we find that the impact of glacier retreat on coarse sediment yield may then vary substantially according to the geometry and storage trends of the newly exposed valley floor; the timing of that response may also be dictated, and potentially obscured, by stochastic and/or extreme events.

show abstract

Heterogeneous Changes in Western North American Glaciers Linked to Decadal Variability in Zonal Wind Strength

Cited by 80 publications

References 62 publications

Regional influence of ocean–atmosphere teleconnections on the timing and duration of MODIS-derived snow cover in British Columbia, Canada

Regional influence of ocean–atmosphere teleconnections on the timing and duration of MODIS-derived snow cover in British Columbia, Canada

Observations on the May 2019 Joffre Peak landslides, British Columbia

Spatial and temporal controls on proglacial erosion rates: A comparison of four basins on Mount Rainier, 1960 to 2017

Contact Info

Product

Resources

About