LANGMUIR LABORATORY ACTIVITIES
Summer 2004

Time-of-Arrival Lightning Mapping System - June through September

Steve Hunyady - New Mexico Tech
Graydon Aulich - New Mexico Tech
Bill Rison - New Mexico Tech
Ron Thomas - New Mexico Tech
Paul Krehbiel - New Mexico Tech
Bill Winn - New Mexico Tech

The lightning mapping array (LMA) used in the STEPS program in 2000 has been reconfigured along with some newer portable instruments that use solar power and batteries. The array is being used in the vicinity of Langmuir Laboratory, with instruments located near Highway 60, in Magdalena, at nearby ranches, and in the forest around the Laboratory where AC power is not available.

This system, and others like it, are of great importance to many other lightning research programs here, in Oklahoma, and at NASA in Alabama. Data from the LMA are widely used in tandem with other instruments and data-collection systems.

Currently the LMA is being configured for real-time display.

More details about this LMA research can be seen in a recent National Geographic article. You can learn about how the array works and see results from previous years at 3D Lightning Mapping System.

Richard Sonnenfeld - New Mexico Tech
Ken Eack - New Mexico Tech
Bill Winn - New Mexico Tech
Steve Hunyady - New Mexico Tech
Graydon Aulich - New Mexico Tech
John Battles - New Mexico Tech

Balloon-borne instruments are being developed to determine the electrical forces from charge carried by lightning channels inside thunderclouds. The new instruments will take advantage of recently developed arrays of special radio receivers that show where lightning propagates inside thunderclouds (LMA - Lightning Map ping Array). With the combination of balloon-borne instruments, radio pictures of lightning, and radars, the immediate goal is to learn how lightning is initiated, how much electrical charge is required for the propagation of lightning channels inside clouds, and how lightning is related to the air motions and precipitation of thunderclouds. The long-term goal is to be able to deduce some of the properties of thunderstorms, including beneficial and damaging effects, from the characteristics of the lightning they produce.

[These activities are funded in part by NSF Grant ATM 0331164 and the New Mexico Space Grant Consortium.]

Charles Moore - New Mexico Tech
Bill Rison - New Mexico Tech
Graydon Aulich - New Mexico Tech
Ken Eack - New Mexico Tech

Pairs of sharp and blunt lightning rods on 20-foot masts are arranged around the Kiva on South Baldy Peak to study their responses when lightning strikes. Other types of commercially-available air terminals are also installed to examine their effectiveness. High-speed digitizers measure currents flowing during both naturally-occurring lightning and triggered lightning events. Recent results have been published in Geophysical Research Letters,and JAM and a 2000 press release reported that blunt rods performed better than traditional sharp lightning rods in this study.

Bill Winn - New Mexico Tech
Steve Hunyady - New Mexico Tech
John Battles - Physics Graduate Student - New Mexico Tech

The electric field monitoring system at the Laboratory is being reprogrammed to work under the Linux operating system, and a low-cost electric field meter is being designed. The monitoring system helps determine when lightning is likely to occur naturally or when it can be triggered by firing small rockets into the cloud overhead (although no triggering is planned for this summer). (Read more about triggering lightning.)

John Battles is designing an electric field meter to replace the very old upward-facing field mills that have been used at Langmuir Laboratory since around 1970. They must function properly when rain falls onto them. (Read more about the E100 field mills.)

Robert Marshall, Umran Inan - Stanford University
Mark Stanley - Los Alamos National Laboratory

A high-speed (up to 10,000 fps) intensified CCD camera mounted on a 14" Dobsonian telescope will be used for high time/spatial resolution measurements of streamer structure in sprites. This work will be of interest to those studying sprites as well as to researchers looking at spark discharge, since streamer velocities are very difficult to measure in the laboratory environment. Previous experiments at Langmuir Lab showed telescopic images of sprites, but the normal video rates used were too slow to measure streamer velocities and time evolution.

Matthew McHarg - US Air Force Academy, Colorado
Hans Stenbaek-Nielson - University of Alaska

Conduct high-speed multi-anode photometric spectral measurements of sprites and lightning with funding provided by NSF. These observations will be made in collaboration with those done by the Stanford researchers.

Davis Sentman - University of Alaska

This project is a continuation of work begun in the summer of 2003 to look for very weak oxygen 630 nm-wavelength emissions from F-region heating by lightning. Two Apogee Ap6E slow scan cooled bare CCD cameras with filters will be used, along with some security-type TV cameras to make ground-based sprite survey/patrol measurements.

Ken Eack - New Mexico Tech
Bill Beasley - University of Oklahoma
Graydon Aulich - New Mexico Tech

Testing continues this summer with balloon flights from Norman, Oklahoma, of an instrument that can record changes in electric field and x-ray or gamma emissions at altitudes up to and above the tops of storms. It is used to test hypotheses for the production of transient luminous events, such as red sprites and blue jets. These events have been observed in the middle atmosphere above thunderstorms. In collaboration with scientists at Los Alamos National Lab and the National Severe Storms Lab, this team hopes to gain a new understanding of lightning discharge processes, the role of runaway electron processes in initiation of discharges, and the development of lightning leaders. [Funded in part by NSF Grant ATM 0075730.]

Carl Popp - Principal Investigator - New Mexico Tech

A weather station at Microphone Hill records half-hour averages of wind speed and direction, temperature, humidity, TH index, barometric pressure, wind chill, and precipitation. Planning is in progress for making the data available on-line. Sampling of precipitation and continuous monitoring for O3 and NOx will continue, as well as sampling for hydrocarbons of various kinds.

Doug Moore - University of New Mexico

Biologists with the Long Term Ecological Research program at the Sevilleta National Wildlife Refuge in central New Mexico continue to look at various plant, rodent, and arthropod populations at sites in the vicinity of Langmuir Lab, and will continue to operate a meteorological data station at the Lab. They are also analyzing population fluctuations in mammals for possible correlation with broad climatic data. (See the UNM Sevilleta LTER informational pages.)

Claret-cup cactus is unusual in that it contains populations of hermaphroditic plants in the center of the range, but is dioecious (separate sexes) on the edges of its range. Colonies near Langmuir Lab appear to be hermaphroditic. Summer is testing two theories that may explain reasons for the evolution of separate sexes in these plants. She combines field experiments, analysis of allozyme protein from small samples of cactus skin, and a GIS database of information from 20 populations throughout the geographic range of Claret-cup cactus.