Elucidating the Space-Time Structure of Low Level Warm Season Precipitation Processes in the Southern Appalachian Mountains Using Models and Observations

Light rainfall is the baseline input to the annual water budget in mountainous landscapes through the tropics and at mid-latitudes. In the Southern Appalachians, the contribution from light rainfall ranges from 50-60% during wet years to 80-90% during dry years, with convective activity and tropical cyclone input providing most of the interannual variability. The Southern Appalachians is a region characterized by rich biodiversity that is vulnerable to land use/land cover changes due to its proximity to a rapidly growing population. Persistent near surface moisture and associated microclimates observed in this region has been well documented since the colonization of the area in terms of species health, fire frequency, and overall biodiversity. The overarching objective of this research is to elucidate the microphysics of light rainfall and the dynamics of low level moisture in the inner region of the Southern Appalachians during the warm season, with a focus on orographically mediated processes. The overarching research hypothesis is that physical processes leading to and governing the life cycle of orographic fog, low level clouds, and precipitation, and their interactions, are strongly tied to landform, land cover, and the diurnal cycles of flow patterns, radiative forcing, and surface fluxes at the ridge-valley scale. The following science questions will be addressed specifically: 1) How do orographic clouds and fog affect the hydrometeorological regime from event to annual scale and as a function of terrain characteristics and land cover?; 2) What are the source areas, governing processes, and relevant time-scales of near surface moisture convergence patterns in the region?; and 3) What are the four dimensional microphysical and dynamical characteristics, including variability and controlling factors and processes, of fog and light rainfall? The research was conducted with two major components: 1) ground-based high-quality observations using multi-sensor platforms and 2) interpretive numerical modeling guided by the analysis of the in situ data collection. Findings illuminate a high level of spatial – down to the ridge scale - and temporal – from event to annual scale - heterogeneity in observations, and a significant impact on the hydrological regime as a result of seeder-feeder interactions among fog, low level clouds, and stratiform rainfall that enhance coalescence efficiency and lead to significantly higher rainfall rates at the land surface. Specifically, results show that enhancement of an event up to one order of magnitude in short-term accumulation can occur as a result of concurrent fog presence. Results also show that events are modulated strongly by terrain characteristics including elevation, slope, geometry, and land cover. These factors produce interactions between highly localized flows and gradients of temperature and moisture with larger scale circulations. Resulting observations of DSD and rainfall patterns are stratified by region and altitude and exhibit clear diurnal and seasonal cycles.

Surface elevation and ice thickness measurements of an airborne radar survey made in the Sør Rondane Mountains, Antarctica

We present surface elevations and ice thicknesses along an airborne radar survey made in Eastern Dronning Maud Land. The survey was carried out above 4 major outlet glaciers which flows around Sør Rondane Mountains with AWI's radar mounted on Polar 5 plane. The data were collected between the 21st and the 23th of January 2011. A full description of the data can be found in Callens et al. (see further detatils).

Drought index from tree-rings in Kongton Mountains, China

The Kongtong Mountain area is a marginal area of the Asian summer monsoon and is sensitive to monsoon dynamics. The sensitivity highlights the need to establishing long-term climate records there and evaluating links with the Asian monsoon. Using "signal-free" methods, we developed a tree-ring chronology based 52 ring-width series from 23 Pinus tabulaeformis and Pinus armandidi trees in the Kongtong Mountain, northern China. Tree growth is highly correlated (0.844) with the Palmer Drought Severity Index (PDSI) from May to July, demonstrating the strength of PDSI in modeling drought conditions in this region. We therefore developed a robust May-July PDSI reconstruction spanning 1615-2009, which explained 71.2% of the instrumental variance for the period 1951-2005. Extremely dry epochs are found in periods of 1723-1727 and 1928-1932, and significant wet conditions are seen from 1696-1700, 1753-1757 and 1963-1969. These persistent dry and wet epochs were also found in northeastern Mongolia, suggesting similar drought regimes between these two regions. The dryness that occurred in the 1920s-1930s was the most severe and was concurrent with a warming period. This warming/drying relationship of the 1920s-1930s may be an analog to the current drying trend in northern China.

Age derminations of rocks from the Read Mountains, Antarctica

The Shackleton Range can be divided into three major units: (1) The East Antarctic Craton and its sedimentary cover (Read Group and Watts Needle Formation), (2) the allochthonous Mount Wegener Nappe (Mount Wegener Formation, Stephenson Bastion Formation, and Wyeth Heights Formation), and (3) the northern belt (basement: Pioneer and Stratton Groups, sedimentary cover: Haskard Highlands Formation (allochthonous?), and Blaiklock Glacier Group). The northern units are thrust over the southern ones. The thrusting is related to the Ross Orogeny. The Mount Wegener Nappe, which appears to be a homogeneous tectonic unit, consists of a Precambrian basement (Stephenson Bastion Formation, Wyeth Heights Formation?) and a Cambrian cover (Mount Wegener Formation). Some questions are still open for discussion: the position of the Haskard Highlands Formation (trilobite shales) may be erratic or represent a tectonic sliver, the relation of the former Turnpike Bluff Group, the origin of the crystalline basement west of Stephenson Bastion and others.

Soil properties and microbial indicators of samples from Lake Wellman, Darwin Mountains, Antarctica

Four pedons on each of four drift sheets in the Lake Wellman area of the Darwin Mountains were sampled for chemical and microbial analyses. The four drifts, Hatherton, Britannia, Danum, and Isca, ranged from early Holocene (10 ka) to mid-Quaternary (c. 900 ka). The soil properties of weathering stage, salt stage, and depths of staining, visible salts, ghosts, and coherence increase with drift age. The landforms contain primarily high-centred polygons with windblown snow in the troughs. The soils are dominantly complexes of Typic Haplorthels and Typic Haploturbels. The soils were dry and alkaline with low levels of organic carbon, nitrogen and phosphorus. Electrical conductivity was high accompanied by high levels of water soluble anions and cations (especially calcium and sulphate in older soils). Soil microbial biomass, measured as phospholipid fatty acids, and numbers of culturable heterotrophic microbes, were low, with highest levels detected in less developed soils from the Hatherton drift. The microbial community structure of the Hatherton soil also differed from that of the Britannia, Danum and Isca soils. Ordination revealed the soil microbial community structure was influenced by soil development and organic carbon.

Opportunities and constraints of transhumant small ruminant production in the Chinese Altay Mountains

This PhD thesis focuses on current livelihoods of agro-pastoral livestock keepers, their animal nutrition, herd and rangeland management strategies. It thereby aims to contribute to sustainable rangeland management, livestock production and household income in Qinghe county of the Chinese Altay Mountain region, located in Xinjiang Uyghur Autonomous Region, PR China. In its first part the study characterizes the socio-economic situation and agricultural practices of agro-pastoralists through structured household interviews. The second part provides insights into the grazing behaviour and feed intake of small ruminants on seasonal pastures in this region, and into the quantitative and qualitative biomass offer on natural rangelands. The third part analyses the reproductive performance and annual growth of the local sheep and goat herds, and, by modelling improved feeding and culling strategies, tests herd management options that potentially improve the monetary output per female herd animal without increasing the pressure onto natural rangelands. Taken together, the results of the study suggest that, despite an increase and intensification of cropping and vegetable gardening in the region of Qinghe, livestock rearing is still the major livelihood strategy both in terms of prevalence and relative importance. However, livestock keeping is challenged by low biomass production on rangelands, due to the combined impact of high climate variability and highly localized grazing pressure on the seasonal pastures. Though government regulations try to tackle the latter aspect, their implementation is sometimes difficult. Alternatives to strict regulation of grazing periods and animal numbers on seasonal pastures are, in the case of goats, more rigorous culling strategies and, in the case of sheep and goats, strategic supplementation of the animals in the winter and spring season. However, for the latter strategy to become economically viable, an improvement of live animal and meat marketing options and an investment in local meat processing facilities that add value to the carcasses is needed. As the regional cities grow rapidly, the potential market to absorb diverse and good quality meat products is there, along with the road network connecting Qinghe county to the regional capital. Such governmental measures will not only create new job opportunities in the region but also benefit the cash income of pastoralists in this westernmost region of China.

Of Mountains and Men : Vision and Memory in Wordsworth and Petrarch

Artikeln visar hur både Petrarca och Wordsworth använder sig av kyrkofadern Augustinus' teorier och personliga exempel tagna från hans Bekännelser

Convective Cold Pools over the Atlas Mountains and Their Influence on the Saharan Heat Low

The West African Monsoon (WAM) and its representation in numerical models are strongly influenced by the Saharan Heat Low (SHL), a low-pressure system driven by radiative heating over the central Sahara and ventilated by the cold and moist inflow from adjacent oceans. It has recently been shown that a significant part of the southerly moisture flux into the SHL originates from convective cold pools over the Sahel. These density currents driven by evaporation of rain are largely absent in models with parameterized convection. This crucial issue has been hypothesized to contribute to the inability of many climate models to reproduce the variability of the WAM. Here, the role of convective cold pools approaching the SHL from the Atlas Mountains, which are a strong orographic trigger for deep convection in Northwest Africa, is analyzed. Knowledge about the frequency of these events, as well as their impact on large-scale dynamics, is required to understand their contribution to the variability of the SHL and to known model uncertainties. The first aspect is addressed through the development of an objective and automated method for the generation of multi-year climatologies not available before. The algorithm combines freely available standard surface observations with satellite microwave data. Representativeness of stations and influence of their spatial density are addressed by comparison to a satellite-only climatology. Applying this algorithm to data from automated weather stations and manned synoptic stations in and south of the Atlas Mountains reveals the frequent occurrence. On the order of 6 events per month are detected from May to September when the SHL is in its northernmost position. The events tend to cluster into several-days long convectively active periods, often with strong events on consecutive days. This study is the first to diagnose dynamical impacts of such periods on the SHL, based on simulations of two example cases using the Weather Research and Forecast (WRF) model at convection-permitting resolution. Sensitivity experiments with artificially removed cold pools as well as different resolutions and parameterizations are conducted. Results indicate increases in surface pressure of more than 1 hPa and significant moisture transports into the desert over several days. This moisture affects radiative heating and thus the energy balance of the SHL. Even though cold pool events north of the SHL are less frequent when compared to their Sahelian counterparts, it is shown that they gain importance due to their temporal clustering on synoptic timescale. Together with studies focusing on the Sahel, this work emphasizes the need for improved parameterization schemes for deep convection in order to produce more reliable climate projections for the WAM.

AQUATIC OLIGOCHAETA (ANNELIDA, CLITELLATA) OF THE Great Smoky Mountains National Park, North Carolina and Tennessee

ID: 8906; issued December 19, 2000

The Aquatic Oligochaeta (Annelida, Clitellata) of the Great Smoky Mountains National Park, North Carolina and Tennessee, USA

ID: 8987; Annual Project Report for 2003, Project No. DLIA 2003-14 issued August 17, 2004

Program for the Fall 2015 MARAC Meeting: Moving Mountains: Ingenuity and Innovation in Archives

The program for the Fall 2015 MARAC meeting, "Moving Mountains: Ingenuity and Innovation in Archives" held October 8-10 in Roanoke, Virginia.

THE PROSPECT OF BIOGAS AMONG SMALL-HOLDER DAIRY GOAT FARMERS IN THE ULUGURU MOUNTAINS, TANZANIA

Biogas can be a clean cooking alternative where biomass is the dominant source of cooking energy and where feedstock for anaerobic digestion is available. By substituting woody biomass for energy, biogas may reduce local deforestation. Tanzania has more than 15.6 million goats. Dairy goats of different breeds are found in the mid- to high altitudes of the country. Population density has made firewood increasingly scarce and there are few energy alternatives in mountainous areas such as in the Uluguru Mountains. In Mgeta ward, Morogoro region, introduction of Norwegian dairy goats in the 1980s has improved livelihoods in the area. In this study, goat manure was assessed as feedstock for biogas and as fertilizer. Field work among small-holder dairy goat farmers in Mgeta was conducted to measure daily manure production, and to provide a basic model for prediction of the quantity of droppings which may be collected by farmers. Biogas and fertilizer potential from goat manure was compared to cow and pig manure. Buswell’s formula was used to calculate approximate methane yield. The results show that goat manure from Mgeta can yield 167 l∙kg Volatile Solids-1 (VS). Compared with other substrates approximate methane yield can be ranked as pig > guatemala grass > cow > goat. The average goat of 25 kg in Mgeta leaves 61 kg Total Solids (TS) droppings per year. It was estimated that 15 goats capita-1 would be required to meet the total cooking energy needs of small-holder households in the study location. N:P:K content in goat manure (TS) is 2:1:1, similar to cow and pig manure. Goat droppings had to be macerated to reduce particle size for anaerobic digestion. Biogas from dairy goats could be combined with the year-round irrigated horticulture production in Mgeta. Vegetable gardens in the slope below the digesters could be fertilized by gravitation with the NH4+-rich bioslurry, to save labour and increase yields.

Effects of bubbles, cracks, and volcanic tephra on the spectral albedo of bare ice near the Transantarctic Mountains: Implications for sea glaciers on Snowball Earth

Spectral albedo was measured along a 6 km transect near the Allan Hills in East Antarctica. The transect traversed the sequence from new snow through old snow, firn, and white ice, to blue ice, showing a systematic progression of decreasing albedo at all wavelengths, as well as decreasing specific surface area (SSA) and increasing density. Broadband albedos under clear-sky range from 0.80 for snow to 0.57 for blue ice, and from 0.87 to 0.65 under cloud. Both air bubbles and cracks scatter sunlight; their contributions to SSA were determined by microcomputed tomography on core samples of the ice. Although albedo is governed primarily by the SSA (and secondarily by the shape) of bubbles or snow grains, albedo also correlates highly with porosity, which, as a proxy variable, would be easier for ice sheet models to predict than bubble sizes. Albedo parameterizations are therefore developed as a function of density for three broad wavelength bands commonly used in general circulation models: visible, near-infrared, and total solar. Relevance to Snowball Earth events derives from the likelihood that sublimation of equatorward-flowing sea glaciers during those events progressively exposed the same sequence of surface materials that we measured at Allan Hills, with our short 6 km transect representing a transect across many degrees of latitude on the Snowball ocean. At the equator of Snowball Earth, climate models predict thick ice, or thin ice, or open water, depending largely on their albedo parameterizations; our measured albedos appear to be within the range that favors ice hundreds of meters thick. Citation:

A lava park in Spain

The lava park is surrounded by the volcanic mountains of Les Preses, revealed as the edges of a vast caldera and repeated at a human scale with low walls made up of small volcanic boulders. These walls are evidence of how successive communities have gradually worked amongst this lava flow to create arable land, supported by rich soils. The people saw the land prosper and learned how to maximise its productivity. Boulders that had come to the surface during agricultural cultivation were moved with human labour to create "artigas“, the characteristic pilings of volcanic stone. They have been used to raise and lower areas, to create shelter and exposure for their crops and to make caves for storage. Amongst all this, paths weave and cross. The whole place is made up of grey and black rocks with a constant cover of green crops or grass.

The big blue

For the 1.5 million travellers who annually visit the Blue Mountains to experience the Australian Bush, it just got closer. The Echo Point redevelopment by Tract Consultants is a megastructure in the void.