Ulyana Horodyskyj: Rates of change on Spillway Lake, Ngozumpa Glacier, Nepal

Rates of Change on Spillway Lake Ngozumpa Glacier, Nepal

Ulyana N. Horodyskyj

University of Colorado Boulder

July 14, 2013

Trail Map

• Background

• The beginning: 2011 time-lapse of supraglacial ponds

• 2012/13 supraglacial ponds + Spillway Lake changes

• Sherpa-Scientist Initiative

• Pilot project in Cordillera Blanca

Melting glaciers

Supraglacial lake formation

rising temperatures

central and eastern Himalaya greatly affected

due to lower angle (slopes) of glaciers

Loss of life and infrastructure

Increase in flood potential

Enhanced melting

Warming climate

1985 - Dig Tsho outburst ($1.5 million damages)

due to storage of water in lakes

due to exposure of bare ice walls

David Breashears, GlacierWorks

Snapshots of Change

N

N

N

Khumbu

Imja

Ngozumpa

Ngozumpa Glacier, Nepal

BBC

Side View

Ngozumpa Glacier

Cho Oyu

18 km

BBC

1951

2009 - Breashears

Project Objectives

1. Use time-lapse photography from melt seasons to qualitatively

and semi-quantitatively document lake changes.

2. Document terminal (spillway) lake area and depth changes,

to determine growth rates through time.

3. Quantify some physics of lake deepening and expansion.

Back in 2011...

Time-Lapse Locations

2010

Dcam

Ucam

300 m

2012

Dcam

Lake X

Ucam

300 m

November 2012: Investigating a Spillway Situation

#1

#2

#3

N

#1

#2

Everest Base Camp 2008

Spy Accusations

#3

N

Important Findings:

- Multiple drain/fill events occur throughout a melt season.

- Satellites may mask this volume loss.

- Drainages can occur even post-freeze.

- End of melt season may not mean end of volume loss.

Spillway Lake: Past and Present

Area Changes:

2001-2010

Thompson et al., 2012

Area Changes:

2010-2012

in progress

2010

2012

x

x

x

x

x

x

N

Depth

2010

Thompson et al., 2012

Depth

2012

in progress

Difference

Map

in progress

Inflow

Inflow

NW

NE

Thermal

Characteristics

MAIN

SW

Surface Temperatures

SW Stable Basin

Bottom Temperatures

Inflow influence?

Subaqueous calving?

Surprise Finding: Arsenic

Low (< 9 ppb)

Moderate (10-15 ppb)

High (16-30 ppb)

Very High (> 30 ppb)

November 2012 Training

May 2013

November 2012

Training

Cordillera Blanca

â&#x20AC;˘â&#x20AC;Ż Supraglacial pond comparisons, through the AAC Climber Science Program

Water Chemistry Morphological Changes

Back-wasting and Down-wasting Rates

blackicehimalaya.wordpress.com

www.glacierworks.org