Monday, January 11, 2016

2015 Sioux Falls Annual Climate Summary

The Sioux Falls National Weather Service Office has released their Annual Climate Summary for 2015.  It was a pretty interesting year!  The summary provides a nice combination of how the year fits into historic climate data, seasonal comparisons, patterns during the year, and highlights exciting meteorological events that occurred during the year.  It was a warm (13th warmest) and wet (9th wettest) year, good for regional agriculture.  Perhaps the most exciting event was the derecho which brought ~100 mph straight-line winds to the Garretson area in the early morning of June 22nd.

Check out the summary report for yourself:

2015 Daily Temperature Data for Sioux Falls, SD.  Average highs and lows in brown,
extreme highs and lows in red and blue, respectively.

Sunday, January 4, 2015

2014 Iceland Holuhraun Eruption: The View Four Months In

As 2015 gets underway let's look back at one of the most exciting stories of 2014, the eruption of the Holuhraun basalt lava flow in northern Iceland.  The eruption that began on August 29, 2014 continues going strong in January 2015. As a matter of fact, the eruption has now covered an area of 83 square kilometers (= 64 USD campuses), and it is the largest in Iceland since the 18th century.

The Holuhraun lava in late October (Photo: Egills Aðalsteinsson, Iceland Magazine)

The first sign of activity was an earthquake swarm at the Bárðarbunga central volcano that began on August 16 (about a week after I left Iceland, having taught my annual volcanology field camp there).  There was concern that an eruption might occur under the Vatnajokull icecap which would likely be explosive, potentially disrupting trans-Atlantic air traffic.  However, a dike, manifested by a propagating linear belt of seismicity, fed magma laterally in the subsurface ever farther northeast from Bárðarbunga until the magma reached the surface on August 29 at Holuhraun, site of a late 18th century crater row and lava field. The lateral drainage of magma from under Bárðarbunga is evident from the dramatic subsidence of the caldera at Bárðarbunga, 56 m as of December 19.  This kind of lateral dike propagation has been demonstrated to be significant in other historic and prehistoric eruptions in Iceland.  

Seismicity at Bárðarbunga and propagating along the dike that fed the Holuhraun eruption (Iceland Met Office)

This basaltic lava eruption is the largest since Laki 1783-1784.  The Laki eruption emitted voluminous volcanic gases which resulted in famine in Iceland (fluorine killing livestock) killing ~25% of the population and volcanic fogs (sulfur dioxide) in Europe that killed 10,000's.  Sulfur dioxide emissions during the current eruption have been substantial, resulting in visible atmospheric effects and warnings in downwind parts of Iceland.  However, the volcanic gas emissions have been lower than Laki, sulfur dioxide emissions are estimated to be 7-20% of the Laki emission rates.

At the margin of the Holuhraun lava flow October 2014 (Photo: Karolina Michalczewska, Univ. of Iceland Twitter)

Will the eruption still be going on in summer 2015, for the next offering of the Iceland Volcanology Field Camp?  Only time will tell, and even if the eruption it is unlikely that there will be ready access to the site (currently there is a travel ban in the area).  But we can dream.

Extent of the Holuhraun lava as of December 28, 2014 (Iceland Met Office)

Follow further developments of the Holuhraun/Bárðarbunga eruption at the Iceland Met Office's update page, and take a live video look (at a distance, and weather-dependent) at the "Live from Iceland" site

Thursday, September 18, 2014

Good News for Careers in Earth Sciences

The Washington Post recently published a report on a PayScale survey of employment outcomes for different college majors.  The report is focused on underemployment.  In the report geology is found to be, along with engineering, math, physics, and law, a field where people feel "least underemployed" (now that's a double-negative we can live with).  This news follows other positive reports on employment prospects in Earth sciences (e.g., the AGI's 2014 Geoscience Workforce Report).

Of course not everyone graduates to the job of their dreams from Earth Sciences, or any other major for that matter. Students can maximize their future employment prospects by not only achieving at a high level academically, but also by engaging in undergraduate research and summer internship opportunities.  USD Earth Science faculty provide terrific opportunities for undergraduate research, and our connection with the South Dakota Geological Survey has provided many Earth Science majors summer internships/jobs.

Monday, September 1, 2014

Welcome to the USD Department of Earth Sciences Blog

This blog will serve as the official blog of the Department of Earth Sciences at the University of South Dakota. Earth Sciences faculty will use the blog as a way to highlight events, research, and accomplishments of students and faculty in department. We will also use the blog as a forum for commentary on news, events, and developments in the Earth sciences.

The study of Earth Sciences encompasses not only geology, but also includes meteorology, and oceanography. South Dakota has terrific geology, from the Black Hills and Badlands in the west, to the glacial geology and Sioux Quartzite in the east. The Department of Earth Sciences has a close relationship with the South Dakota Geological Survey with whom we share a building. USD Earth scientists take field trips and do research throughout South Dakota, adjacent states, across the western United States, and around the world (China, Iceland, Greece, and Mongolia in recent years).

Follow this blog to learn more about the University of South Dakota Department of Earth Sciences!

Badlands National Park, South Dakota. Tertiary rocks of the White River Group overlying
the "yellow mounds" paleosol developed in the Cretaceous Pierre Shale. (B. Jordan)