Roundup: Lava Flows, Pollen Grains and Village Projects

Hazards at Ice-Clad Volcanoes: Phenomena, Processes, and Examples From Mexico, Colombia, Ecuador, and Chile

Photo courtesy of the study
Photo courtesy of the study

“The interaction of volcanic activity with snow and ice bodies can cause serious hazards and risks[….] Case studies from Mexico, Colombia, Ecuador, and Chile are described. These descriptions depict the way in which the volcanic activity has interacted with ice bodies in recent volcanic crises (Popocatépetl, Mexico; Nevado del Huila, Columbia; Llaima and Villarica, Chile) and how the lahar processes have been generated. Reconstruction of historical events (Cotopaxi, Ecuador) or interpretation of events from the geological remains (Citlatépetl, Mexico) help to document past events that today could be disastrous for people and infrastructure now existing at the corresponding sites. A primary challenge for hazard prevention and risk reduction is the difficulty of making decisions based on imperfect information and a large degree of uncertainty. Successful assessments have resulted in the protection of lives in recent cases such as that at Nevado del Huila (Colombia).”

Read more about the study here.

 

Ancient pollen reveals droughts between Sierra Nevada glacier surges

The Sierra Nevada region.
The Sierra Nevada region. Courtesy of Wikipedia.

“Hidden below the surface of California’s Central Valley are pollen grains from the Pleistocene that are providing scientists with clues to the severity of droughts that struck the region between glacial periods.

The Pleistocene—the age of mammoths and mastodons—occurred between 1.8 million and 11,500 years ago. For this new study, scientists dug up Pleistocene sediment samples containing buried pollen from the Central Valley. They found that pollen samples dated from interglacial periods—years between surges in the mountain glaciers—predominantly came from desert plants. The same sediments lacked pollen from plants of wetter climates.”

To learn more about the new findings, click here.

 

Adapting in the Shadow of Annapurna: A Climate Tipping Point

02780771-35.3.cover“Rapid climate change in the Himalaya threatens the traditional livelihoods of remote mountain communities, challenges traditional systems of knowledge, and stresses existing socio-ecological systems. Through semi-structured interviews, participatory photography, and repeat photography focused on climate change and its impacts on traditional livelihoods, we aim to shed light on some of the socio-cultural implications of climate related change in Manang, a remote village in the Annapurna Conservation Area of Western Nepal…. Continued development of relevant, place-based adaptations to rapid Himalayan climate change depends on local peoples’ ability to understand the potential impacts of climate change and to adjust within complex, traditional socio-ecological systems.”

To learn more about the study and its findings, click here.

 

 

Glacier stories you may have missed this week – 10/6

California droughts and glacier melts lead to massive Mt. Shasta mudslide

“Experts believe glacial melting, accelerated by the drought, may have released “pockets of water” that destabilized massive ice blocks and causing the debris flow Saturday afternoon in Shasta-Trinity National Forest, officials said.”

Read more about Mt. Shasta mudslide in the Los Angles Times.

 

The culprit of glacier melting – pollution

“When Kaser’s team looked at ice cores previously drilled at two sites high in the western Alps – the Colle Gnifetti glacier saddle 4,455 m up on Monte Rosa near the Swiss–Italian border, and the Fiescherhorn glacier at 3,900 m in the Bernese Alps – they found that in around 1860 layers of glacial ice started to contain large amounts of soot.”

Read more about how pollution melts glaciers instead of rising temperatures in Climate Central news.

 

Cooling of the Earth increases erosion rates

“Every year, billions of tons of rock and soil vanish from Earth’s surface, scoured from mountains and plains and swept away by wind, rain, and other elements. The chief driver of this dramatic resurfacing is climate, according to a new study. And when the global temperature falls, erosion kicks into overdrive.”

Read more about cold climate shrinks mountains in Advancing Science, Serving Society (AAAS) news.

Glaciers are muddying rivers, with drought to blame

https://www.flickr.com/photos/ericleslie/8212279250/in/photolist-cCuW6s-dndS9U-edti9N-5CUoh2-dFUvMh-4YfzPv-cnpRiA-963PNi-dvG5vy-dGjfwN-61HCUp-cE8Vrf-eyqfiG-nXoKTN-6BUxNx-3pWnxe-cE8UT1-28USLJ-28USLj-abgYeY-6BYE3S-6BUxFV-6BYj6E-6BUcMP-4A9txp-kyMExc-8GmWUy-47PCcj-8scuUp-a8KUSA-5CYFmQ-4AdKGC-4LYtr9-81CDP4-nXh4gG-8gbnvM-3wUuC-52FeVn-5cMp6m-3K1an6-8iHxMK-6Sdi8N-cE8Uts-cE8TW9-NMktt-aKU4XH-8iAb3u-7LZc1C-cE8NYh-5hWkDf
Rivers off of California’s Mount Shasta are increasingly becoming brown. (Eric Leslie/Flickr)

Water flowing off snow-capped mountains has the image of being absolutely pure, but the rivers and streams of California’s Mount Shasta are unusually brown, and geologists are pointing at drought as the cause.

News surrounding the drought in California inundates the media, but we often hear about dying crops and brown lawns. This time it’s the tourism and fishing industries that are up in arms.

Paradoxically, the heavy river flows are caused by the same climatic variations that have created drought throughout the state. A dry winter left California’s glaciers exposed to the sun, without their usual protective cover of snow. Hot weather in the summer is rapidly melting them, particularly on Mount Shasta, home to the state’s largest glaciers. The mountain’s porous volcanic soils can absorb some meltwater, but their capacity has been overwhelmed this summer, and the meltwater is causing debris flows, muddying rivers and streams. More commonly known as mudslides, debris flows are flows of water, rock, soil and other organic material that course downslope, becoming destructive torrents when they enter streambeds. They can muddy the waters of rivers that are usually pristine.

http://www.climatecentral.org
Saying California’s drought is spreading quickly is a small understatement. (Climate Central)

This year, the rapid melt of the mountain’s south-facing Konwakiton Glacier has left the McCloud River opaque with volcanic ash. These highly turbid rivers are not novel phenomena. In the past century, severe debris flows like the current one have been witnessed seven times, particularly in the 1924, 1926 and 1930, other dry years for the region, when debris flows blocked roads and railroads, rendering them impassible for days. During this period in the 1920s, the McCloud River was unfishable. The murky waters do not harm the fish, but simply make them nearly impossible to catch.

https://www.dfg.ca.gov/fish/Resources/WildTrout/Waters/images/LowerMcCloudRiver-1200x900.jpg
Fly fishing in California’s McCloud River is one of the many activities to be affected by brown rivers caused by drought. (California Department of Fish and Wildlife)

Fly fishermen, fly fishing tour guides, and local businesses that relying on tourism fear that the current drought, and the associated glacial melt, debris flows and cloudy waters, will be detrimental to the local economy during the fishing season this fall and in the future years. Some fly fishing groups have already cancelled tours that they had booked—another sign of the cascading effects of glacial melt around the world.

For another story on the effects of glacial melt on fisheries, click here.