Sylke Boyd, PhD
Current Courses: (Fall 2017)
Office hours for Fall 2017: M 11-1, W 12:00 – 1:30 pm; F 11:00-1:00 or after arrangement
Courses taught recently:
, Phys3501 Statistical Physics, Phys1101 General Physics 1, , Phys3003 Computer Modeling of Materials (F16), Phys3101 Classical Mechanics (F16), Phys3151-Solid State Physics (spring 2016), Phys1063 Physics of Weather (F2012), ,FYS Bottomdwellers in an ocean of air (fall 2006), Physics of Sound and Music (fall 2005)
Courses that may never come to pass:
This course would take us to Freiberg, Sachsen, Germany. We would explore a beautiful gentle mountain range with an 800-year history of mining.
Student Research Projects:
Jamin Stagg’20 Optical scattering by bullet ice crystals, Summer 2017
Brittney Ferrian’17 Construction of a prototype cloud lidar (collaboration with Dr Kevin Boyd), HHMI Summer 2015, UROP Spring 2016
Morton Greenslit’16 Image analysis program, cloud and halo detection (HHMI Summer 2015, UROP Spring 2016)
Michelle King’16 Image analysis program for all-sky recordings, halo detection (UROP Spring 2015, UROP Spring 2016)
Shelby Richard’14 Image analysis program for all-sky recordings, halo detection (HHMI Summer 2014)
Jieying Jin’15 Development of a 3d ray tracing program in Mathematica (HHMI Summer 2014)
James Froberg ’14 Development of a ray tracing program for halo simulations in Matlab (Summer 2013, UROP Spring 2014)
Stephen Sorensen’14 Halo observations with the All-sky camera (Summer 2013, UROP Spring 2014)
Zach Klassen’14 Climate variability and land use – and analysis of long-term weather records in the upper Midwest (HHMI, Summer 1013)
and Josef Wieber’14
Robert Smith’13 RDX elastic constants in RDX and the influence of voids on the elasticity tensor (Summer 2012, UROP Spring 2013)
Chad Reverman’13 Bulk modulus of RDX and the influence of voids (Summer 2012, UROP Spring 2013)
Matthew Kroonblawd’12 Energy distribution in RDX during shock (Summer 2010, UROP spring and summer 2011)
Jerry Kessler’11 Statistical analysis of 90-year longitudinal weather record in Morris (UROP Spring 2010)
Johanna Martin’10 Water droplet formation in clouds (MAP 2008/9)
Anna Schliep’07 Dislocations in RDX (GIA, URS 2007 poster)
Sound generation by wind in Strings (UROP, finished, presented as poster at MAAPT Fall 2006 meeting, URS 2007 poster)
Sam Geller’07 Monte Carlo Simulations of Vacancies in a Crystal (GIA, active, presented as poster at MAAPT Fall 2006 meeting)
Matt Gravelle ‘05 Point defects in RDX (UROP and GIA, finished, presented posters at URS and CCTCC, coauthor of publication)
If you are interested to collaborate in a research project please do not hesitate to stop by or drop a line by e-mail.
In recent years, my interest has shifted toward atmospheric physics. Droplet formation, cloud formation, ice crystal growth, the use of optical phenomena to observe and measure aerosols, in particular droplets and ice crystals are at the center. Assessment of cirrus cloud coverage belongs to one of the more difficult problems in data collection. Spatial as well as temporal resolution is limited due to their optical properties, the restrictions of terrestrial observations and the evasiveness of cirrus in satellite images. Cirrus clouds often cause ice halos, in particular 22-degree halos. Other halo features, such as parhelia and various other subspecies of complex halo displays can be seen as well. Collecting data on these halos will, as a longitudinal set, allow assessment about the frequency, type and diurnal distribution of cirrus clouds. Hence, an all-sky camera is creating a continuous image record of sky conditions. Software is being developed to analyse these images with respect to cloud presence, cloud classification and in particular for the presence of ice halos. In addition, a lidar prototype is being developed which may add a third dimension to the observational data on the presence of ice crystals.
Previously, my research interest has been in computer simulations of materials, including force field development, molecular dynamics and Monte Carlo simulations. Materials modeling allows to address questions that are either hard to access experimentally, or for which experimental results are in need of explanation. To some degree, reliable models can have predictive power, but also provide insight into the mechanisms of otherwise inaccessible phenomena. A successful computer model for a materials problem rests is based on three elements:
Left to right: 22°Halo and parhelia; 22° and 46° halos, parhelia and upper-tangent arc; sun pillar and a Parry arc; Light pillars above campus; 22° halo in cirrus(photos by S. Boyd); ray tracing in a hexagonal platelet (James Froberg, MATLAB)
Ice crystal: bullet rosette with 4 arms (animation)
These optical phenomena are caused by refraction and reflection in ice crystals that form in the air. Ice crystals may form as hexagonal platelets, columns, pencils, needles, hollow columns and a wide variety of combination forms. Their shapes are related to temperature and supersaturation conditions in their local environment. Observing and interpreting Halo phenomena can give us information about atmospheric conditions in elevated layers without direct probing. This project addresses two questions: (1) How frequent are halo phenomena, and which kinds are observed in our local area? (2) Which ice crystal shapes would favor particular halo appearances in the sky? Such observations and studies are performed throughout locations all over the world, as a means of passive remote sensing, and a pathway to understand cloud composition as it relates to the origin of the clouds. A new allsky camera is currently in the testing phase. It will be installed on the roof of the science building in January 2014.
Stephen Sorensen has been working on controls for the allsky to allow recording images of sky conditions throughout the daylight hours. He will work on the development of an image-processing program to recognize and categorize various halo appearances. James Froberg has developed a MATLAB program that runs statistics on optical rays through ice crystals and provides an angular distribution of the exiting intensity. He will expand this program to 3d ice crystals and to allow for variation in orientation of the crystals through the academic year 13/14.
In Summer of 2014, the camera was installed on the roof of the science building, and is recording. Shelby Richard has developed the image analysis algorithm for halo detection. The program continues to be refined. Jieying Jin has developed a Mathematica code to visualize and manipulate ray paths in hexagonal ice crystals.
The findings and the halo detection algorithm have been presented at the Gordon Research Conference on Radiation and Climate at Bates College in Lewiston, Maine, July 2015. UMM student Michelle King was able to participate in the conference as well. Here is our poster.
2. Weather and climate: I am interested in using long-term weather records to assess local climate variability. After Jerry Kessler’s analysis of a 90-year temperature record taken in Morris MN (2010) it appeared that the minimum temperatures have increased dramatically throughout the record period, while other climate markers were variable and showed no significant trends. Results of the analysis are given here. One could speculate about an increase of water vapor due to an intensification of agriculture throughout the period. The data only included monthly mins, maxes and averages, and were limited to 90 years. During summer of 2013, Zachary Klassen and Josef Wieber conducted an extensive study on twelve locations throughout the Midwest, using daily data and up to 130 years of record-keeping. It is a search process for possible correlations in land-use and variations in climate markers. It appears that the increase in minimum temperatures is a trend observed in all land forms.
Maps of the trends in February minimum temperatures, the August daily temperature range and the January mean temperature. Circle size relates to slope (max +-8°C/100yrs); colored = “+”, white = “-“; all plots use the same scale. Winter minimum temperatures have increased everywhere. The daily range has decreased in rural areas, and slightly increased in urban areas. The January mean temperatures have small and varied trends.
Animations: NPT simulation of a water droplet of 4000 water molecules at 275 K and 1 atm, water particles shown only.
Recent publications and conference presentations:
Brittney Ferrian, Kevin J. Boyd, and Sylke Boyd. Construction of a low-cost LIDAR for cirrus cloud observations, March Meeting of the American Physical Society, Baltimore 2016, APS March Meeting Abstracts.
Michelle King, Morton Greenslit, and Sylke Boyd, Algorithms for ice halo detection in all-sky images. March Meeting of the American Physical Society, Baltimore 2016.In APS March Meeting Abstracts.
Sylke Boyd, Michelle King, and Morton Greenslit, Analysis of Ice Halo Appearances Using an All-Sky Camera. 2015 Gordon Research Conference on Radiation and Climate, Bates College, Lewiston, Maine, July 26-30 2015.
Shelby Richard, Jieying Jin and Sylke Boyd, Data Collection on Cirrus Coverage Using an Allsky Camera, 2014 Summer Meeting: Minneapolis, Minnesota July30 2014.
Stephen Sorenson, James Froberg and Sylke Boyd, Data collection and analysis on Halo displays using an all-sky camera, APS March Meeting 2014, March 3-7 2014, Denver, Volume 59, Number 1.
Zach Klassen, Josef Wieber and Sylke Boyd, Climate Variability and Local Land Use in the Upper Midwest, APS March Meeting 2014, March 3-7 2014, Denver, Volume 59, Number 1.
Chad Reverman and Sylke Boyd, Bulk modulus of RDX crystal, MAAPT Spring Meeting, Minneapolis, 4-27-2013.
Robert Smith and Sylke Boyd, Computational Study of elastic constants of cyclotrimethylene-trinitramine, MAAPT Spring Meeting, Minneapolis, 4-27-2013.
Matthew Kroonblawd and Sylke Boyd, Computer Study of the Effect Voids in RDX Crystals on the Dissipation of Shock Energy and on the Vibrational Eigenmode Spectrum, International Workshop “Progress and Future Challenges in Computational Materials Science”, Bremen Center for Computational Materials Science – BCCMS, University of Bremen, March 28th – 30th 2011.
Sylke Boyd, Jane S Murray, and Peter Politzer, Molecular dynamics characterization of void defects in crystalline (1,3,5-trinitro-1,3,5-triazacyclohexane), J. Chem. Phys. 131, 204903 (2009).
Sylke Boyd and Kevin J Boyd, A computational analysis of the interaction of lattice and intramolecular vibrational modes in crystalline alpha-RDX, J. Chem. Phys. 129, 134502 (2008).
Boyd, K. J. Boyd, Vibrational
properties of RDX, presented as poster at the 16th
Conference on Current Trends in Computational Chemnistry (CCTCC) in
Boyd, M. Gravelle, Computer Simulations Of Point Defects In Crystalline RDX,
presented as poster at the 2006 Gordon Research Conference on Energetic
Sylke Boyd, Matthew Gravelle, and Peter Politzer, Nonreactive molecular dynamics force field for crystalline hexahydro-1,3,5-trinitro-1,3,5 triazine, , J. Chem. Phys. 124, 104508 (2006).
M. Gravelle, S. Boyd, A computer
study of point defects in the RDX crystal, presented as poster at
the 14th Conference on Current Trends in Computational Chemistry
Super Saturday Science: a science experience for girls 5-8th grade (activity: Air pressure)
Just in case you were wondering what a Nischel is…
Personal stuff – for friends and family
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