Baird Glacier, Alaska Terminus Tongue Breaks Off April 2024

On May 3, 2024May 4, 2024 By mspeltoIn Glacier ObservationsLeave a comment

**Baird Glacier terminus tongue gone in April 26, 2024 Landsat image. Red arrow indicates now joined 5 km² proglacial lake. Yellow dots terminus of Baird and North Baird Glacier**

Baird Glacier drains the west side of the Stikine Icefield in southeast Alaska. It is the only glacier of the Stikine Iceifield that did not retreat significantly from 1960-2010. Pelto et al (2013) predicted the onset of significant retreat of this glacier, which like Brady Glacier had been slow to begin retreat despite thinning that was evident when I visited the glacier in 1984. The proglacial lake that has emerged with retreat has an area of 3.25 km² and the glacier retreat is 2800 m from 1990-2024. The North Baird Glacier separated from Baird Glacier in 2019, with a proglacial lake extending downvalley to the tongue of Baird Glacier that separated this lake from the Baird Glacier proglacial lake until April 2024.

**Baird Glacier in Landsat images from 1990 and 2023 illustrating retreat and proglacial lake expansion.**

Baird Glacier in false color Sentinel images from September 10 2023 and May 2 2024. Proglacial lake (PGL) expanded from 3.2 to 5.1 km². Tongue extending upvalley toward North Baird Glacier (NB) broke up in late April, **yellow arrow**.

Baird Glacier in false color Sentinel images from July 2022 and July 2023. Proglacial lake (PGL) expanded from 3.00 to 3.25 km² width of tongue extending upvalley toward North Baird Glacier (NB) has declined from 700 m to 400 m.

In 1990 the Baird Glacier was sitting on an outwash plain, with no lake at the terminus. The North Baird Glacier was 1 km wide where it joined the Baird Glacier. By 2015 the glacier has retreated 750 m and the lake (PGL) has an area of ~1 km². In 2022 the glacier has retreated leading to a lake expansion to 3.00 km². In July 2023 the tongue of ice extending across the front of the North Baird Glacier valley has thinned 40% since July 2022. The tongue remained throughout 2023 into April of 2024 before breaking up. This leaves the main terminus of the glacier more vulnerable to further rapid calving retreat. Baird Glacier is catching up to the rest of the Stikine Icefield that has experienced significant retreat, Dawes Glacier, Patterson Glacier and Great Glacier. With Sawyer Glacier retreating from tidewater in 2023.

Baird Glacier, Alaska Retreat Generates Proglacial Lake

On July 9, 2023April 19, 2024 By mspeltoIn alaska glacier retreat2 Comments

Baird Glacier on 8-11-1990 and 7-6-2023 Landsat images indicating initiaton of retreat and formation of proglacial lake (PGL). The lake is now 3.25 km², retreat has been 2600 m since 1990-yellow dots indicate margin.

Baird Glacier drains the west side of the Stikine Icefield in southeast Alaska. It is the only glacier of the Stikine Iceifield that did not retreat significantly from 1960-2010. Pelto et al (2013) predicted the onset of significant retreat of this glacier, which like Brady Glacier had been slow to begin retreat despite thinning. From 1887 to 1941, the advance totaled ~1 km and from 1941-1980 it advanced ~1 km. The terminus location did not change from 1980-2010. In 1984 I had a closeup look at the terminus from the outwash plain, it was heavily debris covered and lacked crevassing. This indicated a limited velocity, yet the ice was clearly quite thick, and it would take considerable melting to initiate retreat. In this post we examine Landsat images from 1990, 2005, 2013, 2015 and 2023 along with Sentinel images from 2022 and 2023 to identify how the terminus is responding to climate change.

In 1990 the Baird Glacier was sitting on an outwash plain, with no lake at the terminus. The North Baird Glacier was 1100 meters wide at the yellow arrow, just before joining the Baird Glacier. The main Baird Glacier is 1350 m wide at the pink arrow. By 2005 the North Baird Glacier is 900 m wide at the yellow arrow, and the Baird Glacier 1200 m wide at the pink arrow. The terminus appears unchanged in 2005. By 2013 the North Baird Glacier is just 700 m wide at its junction at the yellow arrow and the Baird Glacier just 1100 m wide at the pink arrow. In 2013 two small marginal lakes have appeared at the terminus, red arrows indicating a measurable retreat, had begun, the lakes are 400-600 m across. By 2015 the glacier has retreated 750 m and the lake has an area of ~1 km². In 2022 the glacier has retreated leading to a lake expansion to 3.00 km². In July 2023 the tongue of ice extending across the front of the North Baird Glacier valley has thinned 40% since July 2022. This tongue is poised to breakup later this summer or next. The North Baird Glacier is separated by ~1 km from the Baird Glacier. The proglacial lake has an area of 3.25 km2 and the glacier retreat is 2600 m from 1990-2023.

Larsen et al (2007) using repeat laser altimetry note that North Baird Glacier in its lowest 10 km from the junction with Baird Glacier was losing 2 m per year in ice thickness. From 2000-2009 the thinning rate is even higher, with Baird Glacier main trunk losing 10-20 m in thckness in the lowest 20 km Larsen et al (2009) Baird Glacier is joining the rest of the Stikine Icefield is already in retreat, Dawes Glacier, Patterson Glacier and Great Glacier. With Sawyer Glacier retreating from tidewater in 2023.

2005 Landsat image of Baird Glacier indicating terminus still on outwash plain. and the Baird and North Baird Glacier firmly connected.

2013 Landsat image of Baird Glacier indicating terminus still reaches outwash plain, with two new lakes forming. and the Baird and North Baird Glacier still connected.

2015 Landsat image of Baird Glacier indicating terminus no longer reaches outwash plain, with proglacial lake now formed. Baird and North Baird Glacier no longer connected.

Baird Glacier Retreat Initiation, Alaska

On September 26, 2013 By mspeltoIn alaska glacier retreat, Glacier Observations2 Comments

Baird Glacier drains the west side of the Stikine Icefield in southeast Alaska. It is the only glacier of the Stikine Iceifield that has not retreated significantly since 1960. This is similar to the Juneau Icefield where only the Taku Glacier has not retreated. From 1887 to 1941, the advance totaled about 1 km and from 1941-1980 it advance another kilometer. The terminus had not changed from 1980-2010. In 1984 I had a closeup look at the terminus, it was heavily debris covered and lacked crevassing. This indicated a limited velocity, yet the ice was clearly quite thick, and it would take considerable melting to initiate retreat. In this post we examine Landsat images from 1990, 2005 and 2013 to see how the terminus is responding to climate change. The blue arrows indicate the glacier flow in the Barid Glacier System. Just above the terminus the main Barid Glacier is joined by the North Baird Glacier. About 15 km upglacier of the terminus are two glaciers Witches Cauldron (WC) to the south and Oasis to the north that the Baird Glacier is flowing into instead of being fed by them. This has been the case for sometime. The purple arrows indicate the 2013 snowline near the end of the melt season is at 1300 m. This is high and will lead to a negative mass balance and volume loss for the glacier in 2013. In 1990 the Baird Glacier is sitting on an outwash plain, with no lake at the terminus. The North Baird Glacier was 1100 meters wide at the yellow arrow, just before joining the Baird Glacier . The main Baird Glacier is 1350 m wide at the pink arrow. By 2005 the North Baird Glacier is 900 m wide at the yellow arrow, and the Baird Glacier 1200 m wide at the pink arrow. The terminus appears unchanged in 2005. By 2013 the North Baird Glacier is just 700 m wide at its junction at the yellow arrow and the Baird Glacier just 1100 m wide at the pink arrow. The narrowing of both indicates less ice flow to the terminus, which will lead to retreat. In 2013 two lakes have appeared at the terminus, red arrow. The terminus has begun a measurable retreat, the lakes are 400-600 m across indicating. There will be a continued expansion of these two lakes and a significiant retreat of the main terminus will ensue. This will lead to the separation of the North Baird and Baird Glacier. Upglacier in the Witches Cauldron a series of supraglacial lakes have begun to form as well. Larsen et al (2007) using repeat laser altimetry note that North Baird Glacier in its lowest 10 km from the junction with Baird Glacier was losing 2 m per year in ice thickness. From 2000-2009 the thinning rate is even higher, with Baird Glacier main trunk losing 10-20 m in thckness in the lowest 20 km Larsen et al (2009). Baird Glacier is joining the rest of the Stikine Icefield is already in retreat, Sawyer Glacier, Patterson Glacier and Great Glacier.