Graduate Students

Benjamin Hmiel


PhD Candidate
Entry Year: 2012
Faculty Mentor(s): Vasilii Petrenko

B03 Hutchison Hall
(585) 275-8788, (585) 276-6412
Fax: (585) 244-5689
bhmiel@ur.rochester.edu

Education

  • M.S., Geology, May 2015, University of Rochester
  • M.S., Chemistry, May 2012, University of Rochester
  • B.S., Chemistry, May 2010, University of Delaware

Research Overview

In cold regions of the planet such as Greenland and Antarctica, snow that falls during the year never melts and accumulates into large continental ice sheets.  Compressed snow (firn) becomes more compacted with each subsequent year’s accumulation and eventually transitions into ice below a certain depth.  Firn is a porous medium and as a result of the compression of overlying layers, the pores in the snow transform into bubbles within the ice at depth.  These bubbles trap a portion of the atmosphere within the pores as the firn transitions into ice at the close-off depth.  As a result of this natural process, the ancient atmosphere can be directly sampled by drilling for ice cores in such cold regions. 

My PhD project aims to quantify the amount of 14C of CO2, CO and CH4 that comes to be present in glacial ice.  It has been discovered that the 14C in glacial ice is a result of two separate mechanisms: (1) trapping of atmospheric air that diffuses through the porous firn column at the top of an ice sheet, and (2) direct production by cosmic rays within the ice lattice.  I am attempting to characterize the relative quantities of 14C from each of these two mechanisms through the firn column and shallow ice at Summit, Greenland.  Understanding the relative abundance and distribution of 14C as it transitions into ice will unlock 14C as a new paleoclimate proxy, allowing us to answer more questions about how climate has changed in the past relative to today.  

Selected Publications

Conference Abstracts

  • B. Hmiel, V.V. Petrenko, A.M. Smith, C. Buizert, C. Harth, R. Beaudette, P.F. Place, Q. Hua, B Yang, I. Vimont, R.F. Weiss, J.P. Severinghaus, E.J. Brook, J.W. White (2016). "Understanding the production and retention of in situ cosmogenic 14C in polar firn", IPICS 2nd Open Science Conference, Hobart, Tasmania (Poster)

Teaching

  • 2010-2012 General Chemistry I & II Lab & Lecture TA
  • 2014, Atmospheric Geochemistry Lecture TA

Professional Honors and Awards

  • 2015, GSA Conference Travel Funding Award

Field Experience

  • 2013, May, Summit Station, Greenland
  • 2013, Nov-Dec, Taylor Glacier, Antarctica
  • 2014, May-June, Summit Station, Greenland (Field Leader)
  • 2015, May-June, Summit Station, Greenland (Field Leader)