Desert Wind Research Articles

“Left All Alone in This World’s Wilderness”: Queer Ecology, Desert Spaces, and Unmaking the Nation in Frank Norris’s McTeague

“Left All Alone in This World’s Wilderness”Queer Ecology, Desert Spaces, and Unmaking the Nation in Frank Norris’s McTeague Jada Ach (bio) Nearly everywhere on earth, sand is principally made up of one element—in some places silica, in others limestone. Ninety percent of a grain is almost always just one of those two elements. But the other 10 percent is the percentage with a difference—the percentage that, in its difference, matters—the percentage that can tell us something about the history of a place. —Vanessa Agard-Jones Can you describe that vast and holy desert, a desert that is so old that it once was the sea? No, you can’t. But does that stop you? Never. —Michael Cobb But you have not known what force resides in the mindless things until you have known a desert wind. —Mary Austin “There was no change in the character of the desert,” observes the narrator near the end of Frank Norris’s McTeague. “Always the same measureless leagues of white-hot alkali stretched away toward the horizon on every hand” (236). Just a few sentences later, the narrator describes the “horrible desolation” of Death Valley, where “not a rock, not a stone” interrupts “the monotony of the ground” (236). In almost every paragraph in McTeague’s final chapters, the narrator notes the desert’s refusal to cultivate life and deliver topographical diversity, and at times Norris seems to go out of his way to emphasize the stasis of this region: “on the face of the desert not a grain of sand was in motion” (232). Not a one. However, Norris’s [End Page 175] desert may be more complicated—and more erotic—than what appears “on the face.” Despite its harshness, its relentless invariability, Norris also depicts the desert as uneven, “dazzling,” and shimmering with the “glitter of sand and sky” (236). How is it that the desert can simultaneously contain all these contradictory characteristics? In one passage, we are told that the landscape is both “flat” and marked by “low mounds”; in yet another passage, the “dazzling surface” of the desert instantaneously fades into oblivion (236). An indeterminate landscape that occupies both eastern California and southwestern Nevada, Norris’s Death Valley is a generative “something—something or other,” to use McTeague’s recurrent utterance, that cannot be reduced to binary systems of classification (226). It is this mesmerizing “something” of the American West that simultaneously propels and frustrates McTeague, just as it did countless individuals who “looked westward for the fulfillment of American promises” in the second half of the nineteenth century (Packard 1). But unlike cowboys, outlaws, miners, prospectors, artists, writers, and others who wandered these regions before him, McTeague looks eastward from the western edge of the nation in hopes of finding his sandy wilderness. However, McTeague’s unpredictable Death Valley is a different kind of wilderness than what John P. O’Grady playfully refers to as the “holiday side of the wild” depicted by other nineteenth-century writers such as Henry David Thoreau and John Muir. In Pilgrims to the Wild, O’Grady uses words including “recreational,” “privileged,” and even “dilettantish” to describe environmental writing born from the nineteenth century’s burgeoning conservation movement, a movement that aimed to preserve the nation’s wilderness areas for future use (125). In such writing, “wilderness” is synonymous not with desert lands, but with the “forested, well-watered landscapes” of New England, coastal California, and the American Northwest (125). Rooted in anxieties “leveled at cities…, urbanization, industrialization, and environmental contamination (not to mention immigration),” Theodore Roosevelt’s wilderness ethos defined the wild spaces of the American West as “elite and remote” corrective zones where Anglo-Saxon men could seek refuge from modern urban influences (Mortimer-Sandilands and Erickson 13, 14). Urban anxieties, when combined with the perceived threat of an increasingly feminine [End Page 176] national identity, culminated in what Denise Cruz has called “the hypermasculine discourse of westward-moving imperialism” (488). This growing interest in the (gendered) West contributed to the federal management of wilderness spaces under the designation of national parks, beginning with Yellowstone in 1872. According to Catriona Mortimer-Sandilands and Bruce Erickson, editors...

The Basis and Operation of Windcatcher in Architecture of Iran's Lut Desert Suburbs: Case Study of Shahdad, Iran

Desert's winds in Iran often have high speed and undesirable quality. The architecture of these areas in suburbs of Lut desert has been contrasted to it as well, Iran has gained benefit from using windcatchers in natural ventilation and cooling the air for public and private spaces so much. This has provided hot rest by natural energy and in this direction, the building were breathing. so by advancing the technology and the materials and construction's methods it is gradually forgotten but obtained efficiency and basis of windcatcher during several century is a valuable gift for keeping the house from machine statue. In this regard, previous research studies and surveys with descriptive- analyzing method have been reviewed and applied for the quality of exploiting the basis and operation of windcatchers in today's architecture in Lut desert suburbs, especially the city of Shahdad.

Ancient Iran, the Origin Land of Wind Catcher in the World

In this study, wind catcher originality has been investigated and their ancient kinds in Iran were characterized. Iranian vernacular architecture is full of creativity and innovation which indicate the intelligence and ability. Unbearable heat, especially in the central plateau of Iran, is one of the factors which sometimes can be unbearable and create serious threats for most of the individuals' life in the absence of necessary arrangements. Wind catcher is an engineering architectural masterpiece of earth to deal with this unbearable heat. Wind catcher is among the manifestations and symbols of Persian civilization. It is not exactly obvious that in which city the first wind catcher is built, but medieval travel writers have frequently talked about desert wind catchers in Yazd. History and background of using the wind catcher is unknown due to its position at the highest level of structure and because is the first place at the risk of damage. The wind catcher, belonged to the eighth century AH is the oldest wind catcher which has kept safe from the harmful events in Iran. Architects and designers of this architectural element have applied this element in their designs with understanding the principles of thermodynamics, aerodynamics, heat transfer, material strength and thermal human comfort. However, the historical evidence certainly indicates the use of wind catcher in Iran before the Arabs and the Persian Gulf area. This study seeks to answer the questions such as the identity and origin of wind catcher, the construction technology and its types, as well as proving the Iranian identity of wind catcher and providing the appropriate and scientific responses for the researchers such as Hassan Fathy (famous Egyptian architect) and Abdel Moneim EL Shorbagy (UAE researcher), each of whom have attributed the background of wind catcher to the locations except Iran, by the study of available historical resources and exploring the history of wind catcher in Iran.

They came for the kids and stayed for the teacher: The Desert Winds Community Steel Orchestra

Abstract This descriptive report examines the motivations of adult beginners’ participation in a leisure activity, the Desert Winds Community Steel Orchestra (DWCSO) based in Phoenix, Arizona. The initial adult ensemble was formed in 1983 based on interest created through the Desert Winds Steel Orchestra, a sixth grade steel band. This study examines the second iteration of this ensemble that began in 1997. Motivational factors are divided into factors that contributed to joining the group and those that motivated members to continue participation. DWCSO participants noted children’s influence and musical curiosity as their impetus for joining the ensemble. They continued participating due to a desirable curriculum and methodology, socialization and enhanced sense of well-being.

Estimating total horizontal aeolian flux within shrub‐invaded groundwater‐dependent meadows using empirical and mechanistic models

AbstractWind erosion is a significant environmental problem that removes soil resources from sensitive ecosystems and contributes to air pollution. In regions of shallow groundwater, friable (puffy) soils are maintained through capillary action, surface evaporation of solute‐rich soil moisture, and protection from mobilization by groundwater‐dependent grasses and shrubs. When a reduction in vegetation cover occurs through any disturbance process, there is potential for aeolian transport and dust emission. We find that as mean gap size between vegetation elements scaled by vegetation height increases, total horizontal aeolian sediment flux increases and explains 58% of the variation in total horizontal aeolian sediment flux. We also test a probabilistic model of wind erosion based on gap size between vegetation elements scaled by vegetation height (the Okin model), which predicts measured total horizontal aeolian sediment flux more closely than another commonly used model based on the average plant area observed in profile (Raupach model). The threshold shear velocity of bare soil appears to increase as gap size between vegetation elements scaled by vegetation height increases, reflecting either surface armoring or reduced interaction between the groundwater capillary zone and surface sediments. This work advances understanding of the importance of measuring gap size between vegetation elements scaled by vegetation height for empirically estimating Q and for structuring process‐based models of desert wind erosion in groundwater‐dependent vegetation.

Determination of rare earth elements in dust deposited on tree leaves from Greater Cairo using inductively coupled plasma mass spectrometry

This work aims at monitoring the rare earth elements (REEs) and Th in dust deposited on tree leaves collected inside and outside Greater Cairo (GC), Egypt. Inductively coupled plasma mass spectrometry (ICP-MS) was employed. The concentration of REEs in the collected dust samples was found to be in the range from 1 to 60 μg g−1. The highest concentration of REEs was found in dust samples collected outside GC, in the middle of the Nile Delta. This would refer to the availability of black sands, due to desert wind occurrence during the sample collection, and anthropogenic activities. The limits of detection of the REEs ranged from 0.02 ng g−1 for Tm to 3 ng g−1 for Yb. There was an obvious variation in the concentration of REEs inside and outside GC due to variations of natural and anthropogenic sources. Strong correlations among all the REEs were found.

Warp Thread

Warp Thread Leslie Hsu Oh (bio) Mom and I breathed deeply four times in the cool shadow of Table Mesa. In the distance, a worn road led southward through the Navajo reservation and northward to Shiprock, New Mexico. The white tips of Dibe Nitsaa, Mount Hesperus, the sacred mountain of the North, whispered above. We stretched our arms into a sky as turquoise as the stone in the necklace Mom made me. Father Sky. Swollen gray clouds drifted slowly by. Then we folded ourselves in two; our fingertips brushed the red soil swirling about our feet. Mother Earth. Mom’s eyes remained closed as she inhaled one more time and brought her arms to her chest, the way she normally embraced me with all her might. I wanted to melt there but instead I stood awkwardly beside her, trying to mime a graceful pattern of arm and leg movements that resembled Tai Chi. We faced East (thinking), then South (planning), West (living), and North (wisdom). Her short black hair settled into a curly halo around her beautiful round face, now unbelievably serene compared to moments earlier when she had slammed her hand-carved weaving fork on the table and said, “Your Rez Mom sucks at this.” “Me, too,” I’d confessed. Our placemat-sized rugs continued to turn into hourglass shapes, no matter how many times we warned each other to think “loose.” A few feet away from our meditation, five Caucasian women sat Indian style on tarps or folded Pendleton blankets. Before them, their looms displayed nearly finished rugs, which would soon win awards. Mothers, wives, grandmothers—all of them set aside these roles for five days to camp with no electricity or water on Master Weaver Sarah Natani’s ranch. The desert wind tangled wisps of blond and sandy brown hair loose from traditional Navajo [End Page 37] buns at the base of their necks. The sun baked their skin. Stray dogs dozed on their laps. Ants about the length of fingernails scuttled between their toes. Odors of sheep and llama dung wafted from the corrals a few feet away. But they didn’t care. They appeared more authentic as Navajo weavers than Mom and I, weaving comfortably air-conditioned within the Natani home. And then, because we stayed at a hotel for the sake of my two-year-old daughter who spent our class time in a Shiprock daycare, we rolled in late every morning with cups of Starbucks steaming in our hands. I wondered what the other weavers thought about us, especially when Mom, who was the only student of Navajo heritage, had to weave with rubber gloves because the yarn irritated her skin. Mostly, they kept a respectful distance, maybe because we called Sarah Natani, Shinaali’ (paternal Grandmother). Mom’s paternal grandfather’s clan, Bit’ahni or Folded Arms People, is a sister clan to Sarah Natani’s maternal clan, Hooghan lani or Many Hogans. Everyone probably thought I was Navajo too, because I shared Mom’s skin and hair color. My expression of K’é (a Navajo tradition of introducing oneself through kinship terms), which I usually stumbled through clumsily, goes something like this: “I was born in Raleigh, North Carolina, to Auxilia Chow of Shanghai, China, and John Hsu of Anhui, China. My Chinese name means Fragrant Grass. Ursula Knoki-Wilson of the Táchii’nii, or Red-Running-into-Water People, Clan adopted me after Mā Ma died of liver cancer. My Navajo name means Journey with Caring or Journey to Bring out Gifts.” The hot desert air seared my lungs and I began to sputter. Mom winked at me and threw her hands into a sky that was supposed to swallow our sorrows, but I couldn’t concentrate. No matter how much Mom loved me like the daughter she never had and tried to caulk the cracks in my grieving heart, I have always felt untethered. I could relate to something Shinaali’ Sarah’s best student had said when she refused a Navajo man’s commission to weave a Navajo rug for him: “Oh no! I’m white. I can’t. It’s not right.” Shinaali’ Sarah was sitting in front of...

The influence of air-suspended particulate concentration on the incidence of suicide attempts and exacerbation of schizophrenia

The main objective of this study was to evaluate the role of the concentration of solid air-suspended particles (SSP) in the incidence of mental disorders. The study is based on 1,871 cases, registered in the Beer-Sheva Mental Health Center (BS-MHC) at Ben-Gurion University (Israel) during a 16-month period from 2001 to 2002; 1,445 persons were hospitalized due to exacerbation of schizophrenia (ICD-10: F20-F29) and 426 after committing a suicide attempt using a variety of means as coded in the ICD-10 (ICD-10: X60-X84). Pearson and Spearman test correlations were used; the statistical significance was tested at p < 0.1. A significant correlation between variations of SSP number concentration (N C ) during eastern desert wind during early morning hours and number of suicide attempts, N SU , was found (ρ > 0.3, p < 0.05), whereas correlation between N C and N SU during western air streams (sea breeze) was not observed (p > 0.2). A trend towards positive correlation (ρ > 0.2, p < 0.1) between the N C and number of persons with exacerbation of schizophrenia as manifested in psychotic attack (N PS ) in periods with dominant eastern winds (4-9am, local time) has been observed, while in the afternoon and evening hours (1-8pm local time) with dominant western winds, N C and N PS are not correlated (p > 0.1). Obviously, concentration of SSP is not the one and only parameter of air pollution state determining meteorological-biological impact, involving incidence of mental disorders, although its role can scarcely be overstated. However, since it is one of the simplest measured parameters, it could be widely used and helpful in the daily struggle for human life comfort in semi-arid areas as well as urban and industrial surroundings, where air pollution reaches crucial values. This study may permit determination of the limits for different external factors, which do not overcome threshold values (without provoking avalanche situations), to single out the group of people at increased risk (with according degree of statistic probability), whose reactions to the weather violations can involve the outbreak of frustration points and prevent or alleviate detrimental mental effects.

A Memory of Color

We see a veiled woman standing in the warm light of the desert sun. Her emotion is unreadable, hidden despite the steady gaze of her eyes. Our attention slips beyond the woman to the stultifying desert landscape that takes shape in the curtained window behind her. A solitary leaf and a palm tree emerge, followed by two distant hills and, perhaps, a road. ‘‘Arab Song’’ is an oil-on-burlap piece by the celebrated painter Paul Klee. Though he completed the piece in 1932, Klee was likely painting under the spell of a 1914 trip to Tunisia. Klee’s mastery of color is the point of reference for most art enthusiasts. Consider his stunning ‘‘Red Balloon,’’ or the depth and vibrancy of ‘‘Ad Parnassum.’’ Indeed, Klee’s Bauhaus lectures on form and design have become classics on color theory (Klee 1999). However, color did not come easily to him. Early in his career, Klee wrote of the ‘‘realization that a long struggle [lay] in store for me in this field [of color]’’ (Klee and Klee 1964). His early paintings lack dramatic impact. That all changed in 1914, when Klee sailed from Marseilles to Tunis with painters August Macke and Louis Moulliet. In the clear light of North Africa, among the brilliant colors of the city and the millennium-old traditional cloth dyes used on the carpets, blankets, and tunics of the souk, Klee experienced the longdesired moment of artistic epiphany. ‘‘Color possesses me, I don’t have to pursue it,’’ Klee wrote. ‘‘Color and I are one. I am a painter’’ (Klee and Klee 1964). Klee returned from Tunisia with that bright, clear image of the landscape imprinted in his mind. He also returned with the ability to use color beyond physical description; he had achieved abstraction. Many of his following works evoked the dramatic geometry and geography of North Africa, in the form of ‘‘shifting horizontals’’ or ‘‘overlapping color squares’’ (Phillips Collection 2011). In ‘‘Arab Song,’’ we see a vivid moment at the turning point of his career, the moment of realization that color had arrived. The tonality and shape are more simplistic than in many of Klee’s other works, but the layers shift and flutter like a curtain in a hot desert wind. We simultaneously see distant hills and gazing eyes, a landscape and a woman, so that one cannot exist without the other. This is a portrait and a landscape, a ‘non-portrait’ and a ‘nonlandscape’ (Heath 2008). It evokes the mystery and power of women as seen in the mind of the artist. It also reminds us of the crucial part that women play in shaping landscapes and lives in the developing world. They preserve traditional roles as they manage crop-planting and livestock-raising, yet they act as the most critical agents of effective and sustainable change in local communities. For Klee, his trip to Tunisia stayed with him throughout his life, stamped into his art with a daring to push color to the limits while maintaining the subtlety of form. In this way, his work mirrors the Tunisian landscapes Correspondence to: Sara E. Howard, e-mail: howard@ecohealthalliance.org; Peter Daszak, e-mail: daszak@ecohealthalliance.org; EcoHealth DOI: 10.1007/s10393-011-0733-7

The influence of several changes in atmospheric states over semi-arid areas on the incidence of mental health disorders

The incidence of suicide attempts [Deliberate Self Harm (DSH); ICD-10: X60-X84] and psychotic attacks (PsA; ICD-10, F20-F29) in association with atmospheric states, typical for areas close to big deserts, was analyzed. A retrospective study is based on the 4,325 cases of DSH and PsA registered in the Mental Health Center (MHC) of Ben-Gurion University (Be'er-Sheva, Israel) during 2001-2003. Pearson and Spearman test correlations were used; the statistical significance was tested at p < 0.1. The influence of temperature and humidity on suicide attempts (N(SU)) and psychotic attacks (N(PS)) was weakly pronounced (p > 0.1). Correlation coefficients between N(SU) and N(PS) and speed WS of westerly wind reaches 0.3 (p < 0.05), while their dependence on easterly WS was weaker (p > 0.09). Variations in easterly wind direction WD influence N(SU) and N(PS) values (p < 0.04), but no corresponding correlation with westerly winds was found (p > 0.3). Obviously ,in transition areas located between different regions ,the main role of air streams in meteorological-biological impact can scarcely be exaggerated. An unstable balance in the internal state of a weather-sensitive person is disturbed when the atmospheric state is changed by specific desert winds, which can provoke significant perturbations in meteorological parameters. Results indicate the importance of wind direction, defining mainly the atmospheric situation in semi-arid areas: changes in direction of the easterly wind influence N(SU) and N(PS), while changes in WS are important for mental health under westerly air streams. Obviously, N(SU) and N(PS) are more affected by the disturbance of weather from its normal state, for a given season, to which the local population is accustomed, than by absolute values of meteorological parameters.

Fathers

Fathers William Wallis (bio) (for Yehuda Amichai, Sept. 22, 2000) My father also moves in light now, outwardBound in fading shadow. On extreme horizons—Waking windows, phantasms of twisting shards—So many final things circle in the son,Myself on the way to the airport, I readBlack-on-white, he was gone up from the city of gold.Those streets glow now with words set burnishedIn the solid walls of his still verse—b'zal el.We met once, word-father, in the city of angels.I pressed your flesh among the celebrities.Behind you, sunset streaked across this plastic pale,As your quick eye sketched desert wind in moonlit trees.The soldier has gone, his midnight arms unwind;The poet sings eternal in fields of the mind. October 2000 William Wallis William (Zev) Wallis's Selected Poems 1969–99 was nominated for the Pulitzer Prize in 1999, and his novel Hawk was awarded the Benjamin Franklin Award for Popular Fiction in 2006. His ode entitled "Writing" appears in Maven in Blue Jeans, a Festschrift in Honor of Zev Garber (Purdue University Press, January 2009). He is professor and Vice-chair of English at Los Angeles Valley College, where he also taught Yiddish Literature in Translation in the Jewish Studies Department. Copyright © 2009 Purdue University

Characteristics of near-surface wind regimes in the Taklimakan Desert, China

Using wind data from 17 meteorological stations distributed throughout the Taklimakan desert, we described the characteristics of the desert's wind regimes and analyzed the spatial and temporal variations in wind direction and sand-drift intensity. The near-surface wind regimes were closely related to general atmospheric circulation patterns and the surrounding topography. There are two prevailing wind directions in the desert. In general, the eastern part of the desert is mainly affected by NE winds and the western part is affected by NW winds. In the area towards the center of the desert, but not around its edges, the monthly mean wind velocity is strongly correlated with the monthly mean temperature. With the exception of Ruoqiang, on the eastern edge of the desert, the drift potential (DP) is less than 200 VU, and the desert thus belongs to a low-energy environment based on Fryberger's classification. In addition, most parts of the desert have an RDP (resultant DP)/DP value greater than 0.4, suggesting that the wind regimes have mainly unimodal or bimodal characteristics. In contrast with the sand-drift intensity, which was highest in the north and east parts of the desert, the highest frequency of sand–dust storms occurred at the southwestern margin of the desert. This results primarily from the differences of dust content on ground surfaces and land use types.

A PIXE and ICP-MS Analysis of Metallic Atmospheric Contaminants in Tree Bark Tissues, A Basis for Biomonitoring Uses*

The qualitative and quantitative metallic content of tree barks of Argania spinosa (L.) Skeels were studied. Argania spinosa is an endemic species in Morocco. This tree is adapted to semi-arid climates and exposed to specific conditions of relative humidity, temperature, wind, and particle transport. Three sites were sampled in Morocco: the large town of Rabat, the harbor of Agadir, and Aït Baha, a countryside location exposed to continuous desert wind. The methodologies included (1) in situ microanalysis with proton-induced X-ray emission (PIXE) and (2) trace element determinations by mass spectrometry with inductively coupled plasma (ICP-MS) associated with extraction procedures. Both methods allowed detection of elements coming from different bark compartments. The profile of airborne contaminants in the barks was typical of the sampling sites. The level of lead in barks sampled in Rabat reached 100 ng cm−2, or higher, while it varied between 3 and 35 ng cm−2 in Aït Baha. The in situ study of the microscopic structure of the bark provided the location of major and minor elements at various depths inside the bark. A differential between free deposit on the bark surface and penetrated content was found for the major and trace elements. The free deposit on the bark surface was suspected to be mostly the result of recent contamination. Part of the contaminants spread out on the surface penetrated the superficial suber. This long-term accumulation affected mostly Pb. In deeper levels, airborne elements at low concentrations and elements resulting from root uptake were concurrently present and resulted in a complex situation, as noted for zinc.

On the variations in the electrical state under specific meteorological conditions in the ground atmospheric layer in semi-arid areas

The object of this study is to evaluate the role of synoptic situations or the combination of several environmental parameters typical for regions close to big deserts, as possible exterior pathogenic factors, which give rise to a number of sometimes medically unexplained symptoms and disorders of human well-being. We suppose that one of the most important causes might be atmospheric electricity, whose role in human life, health and feelings can scarcely be exaggerated; in particular, our research is concentrated on the influence of electromagnetic fields on some subsystems of the human organism. Discussed below are the results of one of the initial stages of our research into the problem of the variations in the electrical state in connection with meteorological conditions in the surface atmospheric layer. The environmental electrical state is determined by either global electrical effects or local factors, as the content of the air column and the meteorological conditions in this volume are tightly connected with air streams. Especially in our region, located between the Mediterranean Sea and the huge African and Asian deserts, the direction, duration and speed of the winds must play the dominant role, due to their control over the content and concentration of air-suspended particles N T . Desert winds bring increased N T of enlarged solid grains, mostly charged, hotter temperature T 0, dryness and other perturbations in the usual weather state and, finally, in the atmospheric electric field intensity E. Within limited intervals of wind speed V w (2–5 m·s −1) and concentration of enlarged solid grains N T (500–4500 grains cm −3), the correlation coefficients between E and N T and V w can reach more than 0.90. Outside these ranges, considerably increased N T or several combinations of wind direction with V w (not necessarily strong winds) lead to the principal change in the values of E and the form of its diurnal distribution from what is usual for stable weather. For moderately polluted air, the dependence of E on N T can be approximated well enough by a polynomial of the second degree; in a dust storm, this function is very close to the log-normal distribution.

Wanderings in the Desert: From the Exodus to the English Patient

Wanderings in the Desert: From the Exodus to the English Patient

Electrostatic field detectors, the seaside, and the desert wind? [PERIFELD-M security fence

In the early 1960s, the first ideas were developed by leading companies in Germany to design an intrusion detection system following a capacitance measurement principle. In 1982, Siemens AG was the first company in this market which analysed all outdoor influences and recognised the essential problems which cause any classic capacitive or electrostatic detector to suffer from high unwanted false alarm rates. The result was that, already in 1984, a complete new peripheral hardware design, with a very high electrical and capacitive stability, was created by Siemens AG which remains state-of-the-art. Nevertheless, even if this high-grade material is installed, it can happen in certain cases that apparently invisible peripheral influences are the cause of important electrical effects. This paper describes a practical case experienced in 1999 where a coincidental combination of seaside conditions and a local desert wind strongly interfered in the physics of a capacitive electrostatic field detector.

Rivers in the Sand

The Eastern Sahara is one of the hottest places on Earth, its par. ched sands moistened by a rair shower every few decades. It may come as a surprise, then, that stretches of this African desert have inspired a scientific debate over water. More specifically, the argument concerns ancient water. From around 2 million to 4,000 years ago, one group ol investigators contends, a braided network of channels set into large valleys in the Eastern Sahara filled with flowing water during extended spells of humidity and substantial rainfall. The valleys attracted early humans at least 200,000 years ago, they say. Another team maintains no such rivei system ever existed. In their view, fierce desert winds hollowed out depressions in the earth that became temporary ponds or lakes after rains. Human activity al these oases was minimal at best, they conclude. One thing is sure: The debate owes its existence to the U.S. space program. The first inkling that the Eastern Sahara once possessed some type ol water drainage system came in 1982, when scientists at the U.S. Geological Survey (USGS) in Flagstaff, Ariz., examined images of Earth taken during a flight of the space shuttle Columbia. The penetrated large areas of the Sahara where the sand sheet is no more than several feet thick, revealing a web ol valleys and smaller channels winding beneath the desert sands (SN: 4/21/84, p.244). In 1984, guided by specially processed maps from Landsat, and other sources, USGS researchers located some of the radar-exposed channels with the aid of a satellite navigation device modified for land use. Excavations on the shores of two sand-covered valleys, directed by archaeologist William P McHugh (who died in May), uncovered hand axes and other stone artifacts dating to approximately 200,000 years ago. The archaeological evidence fits with geological data, described by USGS scientist John F McCauley and his colleagues in the July 1986 IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, indicating the radar are missing links of a previously unrecognized trans-African river system. At least 30 million years ago, the researchers maintain, volcanic eruptions and shifts in the Earth's crust carved out the system's major streams, which flowed southwest from headwaters in Egypt and the Sudan, across northern Africa and into the Atlantic Ocean at the Gulf of Guinea. The Amazonian proportions of the river system gradually receded. Geological disturbances cut off stream flow at several points in the valleys around 15 million years ago, McCauley's group says. A northward-flowing river arose about 6 million years ago and amputated stilloperational sections of the river complex from its headwaters. The onset of extreme heat and virtually no rain around 2 million years ago dealt the final blow. Nevertheless, the USGS researchers hold, ensuing rainy periods temporarily reactivated some of the rivers and streams in the Eastern Sahara. Archaeological remains indicate the streams drew groups of early humans until about 4,000 years ago, when climate changes made the area unlivable.

Desert sedimentary environments, present and past—A summary

Tropical deserts develop where the potential rate of evaporation exceeds that of precipitation, where rainfall is too low or spasmodic to support vegetation. These usually occur in the trade-wind belts north and south of the equator and in the rain shadow of mountain ranges. About half the area of deserts comprise outcrop subject to erosion and deflation. The rest consists of sediments of fluvial (wadi), lacustrine (salina), paralic (coastal sabkha) and aeolian origin, and of evaporites. Ephemeral streams deposit sands and gravels over basin-margin alluvial fans, and over desert plains where sub-surface cementation commonly takes place. Evaporation of basin-centre temporary lakes results in a crust of halite (inland sabkha). Fluvial sands are an important source of dune sand; the finer fractions are removed from the desert in suspension to become loess and the coarser grain remain as a deflation lag. The axes of sand dunes are transverse to moderate winds and parallel to strong winds. Giant forms of the latter dune type were prevalent during the last ice age, and in coastal areas carbonate-cemented dune sands extend below present sea level; this suggests a causal relationship between polar glaciations and strong desert winds. Desert fluvial sediments rarely reach the sea, so the warm and clear coastal waters are ideal for the manufacture of organic carbonates. Longshore currents sweep them into offshore bars behind which evaporitic lagoonal conditions develop. The lagoons become sabkhas as they are infilled with algally bound marine and wind-blown sediment. Although there are desert sequences as old as about 2000 Ma, they seem to have occurred only sporadically during the earth's history. It seems likely that their occurrence was controlled by the past size of continents, their location relative to the equator, by the freedom of circulation of global oceanic water and by the presence of ice caps. The Permo-Triassic was a time of extensive evaporite deposition and dune activity. By implication, other known occurrences of evaporites may be marginal to wadi and dune sequences that have yet to be identified.

Application of in-Air PIXE for Corrosion-Erosion Studies of Metal Surfaces

Two methods are presented to demonstrate the usefullness of In-air PIXE for studying enviromental corrosion and erosion of metal surfaces. (1) Surface adsorption of corrosive vapors on gases in the ppm range is detected with the In-air PIXE technique. The adsorbed chlorine and Argon can be pumped away with moderate (200°C) heating of the metal surface. Therefore such investigation can only be done with the In-air PIXE. (2) Airborne particulates with high velocity, such as sands in the desert wind, can erode metal surface. They can also imbed foreign materials into the metal surface. Those foreign materials may lead to surface corrosion. Metal surface and the glass beads of a sand-blaster, before and after sandblasting, were examined with In-air PIXE to show its sensitivity and the ease with which it can detect minute quantities taken off or imbedded into the metal surface after just a short blasting time.

Habits of the Hypertrophic Blister Beetle, Cysteodemus armatus

The basic ecological and behavioral events fundamental to the existence of Cysteodemus armatus LeConte are revealed. This blister beetle, char- acterized by its inflated elytra, is encountered from April to June along the Colorado River basin and adjacent drainages. Beetles mate and feed on succulent vegetation during the day, and actually remain arborial at night. Courtship is relatively uncomplicated for a meloid, and oviposition occurs in sandy burrows constructed by females. Emergent parasitoid triungulins emigrate to potential hosts, with the aid of the incessant desert wind. Information concerning the life histories of meloid beetles is scarce and, for the tribe Eupomphini, almost non-existent. LaRivers (1938) noted the habits of Cysteodemus armatus LeConte and found this species to be a convenient zoological index to the ecology of several valleys in southern Nevada. Genera of the Eupomphini and Lyttini were characterized by Selander (1954) and, in his descriptions of meloid first instar larvae, MacSwain (1956) included the morphology of C. armatus triungulins. More recently, the bionomics of Megetra, a member of the Eupomphini intensively studied by Selander (1965), was found to closely parallel the mode of existence encountered in C. armatus and C. wislizeni. Related biological information was also included in a taxonomic revision of the Cordylospasta compiled by Pinto (1972). In the present study, I investigated the ecological life history of C. armatus and reported its feeding, courtship, and nest building behavior. ECOLOGY.-Cysteodemus armatus is endemic to the arid south- western United States and Mexico, but this study was limited to its southern range in western Arizona along the Colorado River and its