Investigation of Dust Emission Hotspots in Chihuahuan Desert … · 2016-07-14 · Investigation of Dust Emission Hotspots in Chihuahuan Desert Playa Basins Principal Investigators:

Investigation of Dust Emission Hotspots in

Chihuahuan Desert Playa Basins

Principal Investigators: Thomas E. Gill, UTEP

Miguel Dominguez Acosta, UACJ

Graduate Student Researchers: Nancy I. Rivera Rivera

Adriana E. Perez

Alfredo Ruiz

Sonny Emmert

Sabrina Canalda

THE PROBLEM:

• Windblown desert dust- primarily from

natural sources near the US/Mexico

border in the Chihuahuan Desert region

of Chihuahua, Texas, and New Mexico-

creates intense plumes of particulate

matter (primarily coarse but also fine

particles)

THE PROBLEM:• This dust may advect in from the desert to populated areas

such as El Paso/ Cd. Juarez, Las Cruces, Palomas/ Columbus,

and other cities.

Image from TCEQ Chelsea Street Webcam, El Paso

PM 10 Concentrations 12/15/03

El Paso Hourly

max over 1200

µg/m3

San Antonio- spike to ~900 µg/m3

LRGV- > 600µg/m3

source

receptor

Long-distance

transport

All The Way to Canada

“Dirty

Bomb”

???

In contrast to urban fugitive dust in Chihuahuan Desert border cities, which has

been investigated in a number of projects, these desert dust storms have been very

poorly described and understood. Their sources and transport patterns were only

very crudely known, the specific atmospheric and land-surface conditions that

cause them poorly understood, and the composition and characteristics of these

aerosols and their emitting source materials had not been analyzed. The motivation

of this project was to begin to better understand these “natural” dust events.

Wind Direction of El Paso Dust Events 1932-2006

Where Does It Come From?

What’s There Where It Comes From?Prospero et al. (“Global sources of atmospheric soil dust…,” Reviews of Geophysics 40, 2002) stated,

This, in fact, very well describes the source area of an April 2001 dust event previously studied by the PI: and the major sources of dust on a global basis are known to be dry lake beds recently wet in the geological past, especially where they are associated with large sand deposits.

Image from PACES, UTEP

“In Mexico, there is a substantial but variably active (dust) source

just south of the U.S.- Mexico border… where there is an extensive

system of playas and aeolian, lacustrine and alluvial sediments….

There is a second center of activity farther to the southeast also in

the Basin and Range portion of Mexico.”

The Culprit!!!

(???)

“Remote

sensing

wizardry” was

applied to a

huge database

of satellite

imagery to

detect the

actual source

points of large

dust plumes.

Source

Locations

for Dust

Plume

Outbreaks

(Nancy

Rivera,

UTEP M.S.

Thesis

defended

11/2006)

RESULTS:

YES, PLAYAS ARE

IMPORTANT… but it’s not

that cut and dried.

Lake Palomas- clay playa

White Sands (Lake Lucero/

Lake Otero)- saline playa

About half the dust sources do turn out to be

associated with playas (dry lakes). Especially

important turns out to be the EDGES of playas-

where there is an interface between loose sands

and fine clay and silt particles which become dust.

Desert shrublands/ rangelands not

associated with playas are also an

important contributor- especially areas

with coppice dunes and lots of sand.

Agricultural lands, especially in Casas Grandes

River valley (Chih.) are a small but persistent source

of dust: lands are fallow in windy winter season

NEXT STEP: visit many of these dust source sites (ground

truthing) and characterize their geology/land use, sediment

and soil characteristics, and collect samples for additional

analysis of sedimentology and chemistry.

Passive blowing dust and sand sampling traps were deployed at several sites

and are being monitored regularly.

The remoteness of these sites and the

infrequency of individual dust events

generally precluded active aerosol

sampling. However, an opportunity did

arise to collect aerosol samples at two

sites near the White Sands sources in

2005 thanks to a collaboration with

White Sands Missile Range and two

other universities.

(These data still being analyzed)

Field reconnaissance revealed some surprises. A few anthropogenically dis-

turbed sites were also discovered (cattle corrals, and this site precisely at a dust

source point in the middle of nowhere: anyone know what was going on here?)

Particle Size Distribution

0.01 0.1 1 10 100 1000 3000

Particle Size (µm)

0

2

4

6

8

10

12

Volu

me (

%)

EAST HARBOR GRAB 2 - Average, Monday, August 08, 2005 3:02:22 PM

DRY EASTHARBOR GRAB 1 - Average, Monday, August 08, 2005 3:58:30 PM

PARTICLE SIZE DISTRIBUTION OF DUST-EMITTING SOILS

Measured via laser diffraction

White Sands, saline gypsum playa soil: red line shows particle size distribution

when wet, green line shows when dry.

Notice the double peak (sand and ~ 10µm) in dry White Sands surface soil.



Agricultural soil. Notice the long tail of very fine particles as small as 2 µm.



Near shore of paleo-lake Palomas in Chihuahua. Sequence of three samples

moving from the playa surface (green) to sand sheet away from the shore (blue).

Notice the playa surface clay (particles submicron to a few microns) and fine

particles as small as 1µm, and the three distinct populations of particles: clay,

silt (10- 20 µm) and sand (100- 200 µm).


0.01 0.1 1 10 100 1000 3000

Particle Size (µm)

0

1

2

3

4

5

6

Volu

me (

%)



0.01 0.1 1 10 100 1000 3000

Particle Size (µm)

0

1

2

3

4

5

6

Volu

me (

%)

Wind erosion process: requires both

coarse particles (~100 µm) for saltation

motion close to the ground that

“sandblasts” and “kicks” fine dust

particles into the atmosphere


The environment on and near the edge of many playas (dry lake beds) is

perfect for windblown dust emission due to the presence of sand (provides

the energy and work of saltation and sandblasting) and silt and clay (get

blasted off into the atmosphere as dust aerosols).


0.01 0.1 1 10 100 1000 3000

Particle Size (µm)

0

1

2

3

4

5

6

Volu

me (

%)


0.01 0.1 1 10 100 1000 3000

Particle Size (µm)

0

2

4

6

8

10

12

14

16

Volu

me (

%)

COR 014 (CSa)

COR 015 (CSa)

COR 004 (SSa)

Samalayuca Lake Palomas Corridor Particle Size (μm)

As sand moves downwind towards the Samalayuca dunes, it initially (blue) contains a

“tail” of fine particles (even as fine as submicron), and as the sand bounces downwind

towards the Samalayuca dunes (red) the fine material disappears… where did it go? It

turned to dust and blew out! Natural “winnowing” process cleans the sand and results

in these dust events.

Electron microscopic analysis of particles

recovered from individual dust events reveals

aggregates (clumps) of much finer particles.

X-ray spectrometric elemental analysis of dust

source materials may be usable to gain chemical

“signatures” of individual source types and

assess the possibility of health impacts.

Concentration (Ratioed to "Al")

0 10 20 30 40 50 60 70 80

COR 014 (CSa)

COR 015 (CSa)

COR 004 (SSa)

Iron %

Titanium %

Calcium %

Potasium %

Chlorine %

Sulphur %

Silicon %

Aluminum %

Magnesium %

Sodium %

Metals such as lead, zinc and arsenic have been

detected in individual dust-source soil samples.

Implicatio

ns

Additional Findings-

As well as helping us work

towards answering some

questions, this study has

helped provoke some new

ones as well.

Implicatio

ns

The relatively random

distribution of source

points from event to

event- even within pre-

ferred areas- suggests to

us that the actual

initiation spots of dust

events may be controlled

to a large degree by

small-scale meteorolo-

gical fluctuations

(relatively chaotic), as

opposed to land surface

or geological factors

(relatively predictable).

Additional Findings

Implicatio

ns

Many of the source

points are on the

downwind side of

mountain ranges,

suggesting the possible

role of topography-

enhanced wind flows in

provoking dust

emission: in the future

we hope to be able to

model this and

investigate this

possibility further.

JOURNAL ARTICLE SUBMITTED:

Lee, J.A., T.E. Gill, K.R. Mulligan, M.A. Dominguez, and A.E. Perez, in review. Land use/land cover and point sources of the 15 December 2003 dust storm in southwestern

North America. Submitted to Geomorphology.

CONFERENCE PROCEEDINGS:

Rivera Rivera, N.I., M.P. Bleiweiss, J.L. Hand, and T.E. Gill, 2006. Characterization of dust storms' sources in southwestern U. S and northwestern Mexico using remote sensing

imagery. Preprints of the 14th Conference on Satellite Meteorology and Oceanography, American Meteorological Society, January 2006, Atlanta, GA, #P3.9, 17 pp.

Novlan, D.J., M. Hardiman, and T.E. Gill, 2007. A synoptic climatology of blowing dust events in El Paso, Texas from 1932-2005. Preprints of the 16th Conference on Applied

Climatology, American Meteorological Society, January 2007, San Antonio, TX , #J3.12, 13 pp.

ABSTRACTS OF CONFERENCE PRESENTATIONS:

Cahill, C.F., Y. Yee, T.E. Gill, A. Ruiz, S.P. Emmert, T.A. Cahill, F. Wilson, and E. Ellison, 2005. Springtime dust aerosols at White Sands Missile Range, New Mexico. EOS

(Transactions, American Geophysical Union) 86 (52 supp.): P22B- 02.

Rivera Rivera, N.I., T.E. Gill, M.P. Bleiweiss, J.L. Hand, M.A. Dominguez, A. Ruiz, A.E. Perez, S.P. Emmert, J.A. Lee, and K.R. Mulligan, 2005. Detection and preliminary

assessment of source areas of the 15 December 2003 dust storm in the Chihuahuan Desert, southwestern North America. EOS (Transactions, American Geophysical Union)

86 (52 supp.): H51C-0389.

Emmert, S.P., and T.E. Gill, 2006. Source apportionment and composition of precipitation and wet deposition in the Paso Del Norte airshed. Abstracts of the Eighth Conference

on Atmospheric Chemistry, American Meteorological Society Annual Meeting, Atlanta, GA, January 2006, Abstract #J5.2.

Canalda, S.M., T.E. Gill, and S.P. Emmert, 2006. Long-range transport of particles from regional dust storms originating in the Chihuahuan Desert. Program and Abstracts, New

Mexico Geological Society 2006 Spring Meeting, Socorro, April 2006, p. 10.

Dominguez, M.A., T.E. Gill, and R. Schmidt, 2006. The Lake Palomas - Samalayuca dune corridor system, Chihuahua, Mexico. In: Nickling, W.G., S. Turner, J.A. Gillies and M.

Puddister, editors, Program and Abstracts of the Sixth International Conference on Aeolian Research, Guelph, Canada, July 2006, p. 80.

Rivera Rivera, N.I., T.E. Gill, M.P. Bleiweiss, and J.L. Hand, 2006. Detection and characterization of dust source areas in the Chihuahuan Desert, southwestern North America,

through remote sensing. In: Nickling, W.G., S. Turner, J.A. Gillies and M. Puddister, editors, Program and Abstracts of the Sixth International Conference on Aeolian Research,

Guelph, Canada, July 2006, p. 140.

Lee, J.A., T.E. Gill, K.R. Mulligan, M.A. Dominguez, A.E. Perez, and A. Ruiz, 2006. Land use/land cover and point sources of the 15 December 2003 dust storm in southwestern

North America. In: Nickling, W.G., S. Turner, J.A. Gillies and M. Puddister, editors, Program and Abstracts of the Sixth International Conference on Aeolian Research, Guelph,

Canada, July 2006, p. 142.

Gill, T.E., R.J. Vet, P.E. Biscaye, M.P. Bleiweiss, and M. Shaw, 2006. Recurrent transcontinental dust transport from southwestern North America to Canada. In: Nickling, W.G.,

S. Turner, J.A. Gillies and M. Puddister, editors, Program and Abstracts of the Sixth International Conference on Aeolian Research, Guelph, Canada, July 2006, p. 150.

Project- Related Professional Meetings, Conferences, Symposia, & Workshops Attended:

American Geophysical Union Annual Fall Meeting, San Francisco, CA, December 2005.

American Meteorological Society Annual Meeting, Atlanta, GA, January 2006

UTEP Geological Sciences Colloquium, March 2006

Sixth International Conference on Aeolian Research, Guelph, Ontario, Canada, July 2006.

National Park Service, Chihuahuan Desert Inventory & Monitoring Network (CHDN) Vital Signs Prioritization Workshop, El Paso, TX, August 2006

Undergraduate Research Students:

Canalda, Sabrina (Senior, Geology)- 2005/06.

Graduate Thesis Completed

Rivera Rivera, Nancy I., December 2006 (M.S., Environmental Science, UTEP), “Detection and Characterization of Dust Source Areas in the Chihuahuan Desert, Southwestern

North America.”

4 Additional Graduate Students Supported and/or Perfoming Thesis/Dissertation Research Related To This Project.

6 Or More Journal Articles In Development (should be submitted in 2007) Related To The Findings Of This Project.

2 Additional Proposals Submitted To Date (1 Funded) Related To This Project… More To Come

¿HAY PREGUNTAS?

Documents

Investigation of Dust Emission Hotspots in Chihuahuan Desert … · 2016-07-14 · Investigation of Dust Emission Hotspots in Chihuahuan Desert Playa Basins Principal Investigators: