Has spring snowpack declined in the Washington Cascades?

Our best estimates of 1 April snow water equivalent (SWE) in the Cascade Mountains of Washington State indicate a substantial (roughly 15–35%) decline from mid-century to 2006, with larger declines at low elevations and smaller declines or increases at high elevations. This range of values includes estimates from observations and hydrologic modeling, reflects a range of starting points between about 1930 and 1970 and also reflects uncertainties about sampling. The most important sampling issue springs from the fact that half the 1 April SWE in the Cascades is found below about 1240 m, altitudes at which sampling was poor before 1945. Separating the influences of temperature and precipitation on 1 April SWE in several ways, it is clear that long-term trends are dominated by trends in temperature, whereas variability in precipitation adds "noise" to the time series. Consideration of spatial and temporal patterns of change rules out natural variations like the Pacific Decadal Oscillation as the sole cause of the decline. Regional warming has clearly played a role, but it is not yet possible to quantify how much of that regional warming is related to greenhouse gas emissions

Teknologi Pembuatan Perahu Tradisional oleh Masyarakat di Sekitar Danau Tigi Kampung Puyai

Penelitian ini bertujuan untuk mengetahui jenis kayu dan teknik pembuatan serta pemeliharaan dan pola transfer pengetahuan dari proses pembuatan perahu. Metode penelitian yang digunakan yaitu metode deskriptif dengan teknik wawancara semistruktural dan observasi langsung di lapangan. Hasil penelitian menunjukkan bahwa terdapat 12 jenis kayu dari 7 famili yang digunakan oleh masyarakat Kampung Puyai sebagai bahan baku pembuatan perahu tradisional. Terdapat 3 (tiga) jenis kayu yang sering digunakan untuk badan perahu yaitu Digi (Nothofagus recurva Steenis), Epo (Eugeniaanomala), Danmoane (Toona sp.). Proses pembuatan perahu meliputi pembagian batang, pembentukan perahu, penghalusan, penyelesaian (finishing), penarikan perahu ke danau dan pengujian kelayakan perahu. Pemeliharaan dilakukan untuk mencegah terjadinya  kerusakan perahu antara lain: pembersihan setiap kali pemakaiaan, perbaikan secara menyeluruh, perlindungan terhadap perahu dari panas matahari. Pola transfer pengetahuan pembuatan perahu secara tradisional kepada generasi berikutnya dilakukan dengan cara mengajak para pemuda untuk ikut serta dalam proses pembuatan perahu.&nbsp

Guidelines for constructing climate scenarios

Scientists and others from academia, government, and the private sector increasingly are using climate model outputs in research and decision support. For the most recent assessment report of the Intergovernmental Panel on Climate Change, 18 global modeling centers contributed outputs from hundreds of simulations, coordinated through the Coupled Model Intercomparison Project Phase 3 (CMIP3), to the archive at the Program for Climate Model Diagnostics and Intercomparison (PCMDI; http://pcmdi3.llnl.gov) [Meehl et al., 2007]. Many users of climate model outputs prefer downscaled data—i.e., data at higher spatial resolution—to direct global climate model (GCM) outputs; downscaling can be statistical [e.g., Meehl et al., 2007] or dynamical [e.g., Mearns et al., 2009]. More than 800 users have obtained downscaled CMIP3 results from one such Web site alone (see http://gdo-dcp.ucllnl.org/downscaled cmip3_projections/, described by Meehl et al., [2007])

What causes the irregular cycle of the atmospheric tape recorder signal in HCN?

Variations in the mixing ratio of long-lived trace gases entering the stratosphere in the tropics are carried upward with the rising air with the signal being observable throughout the tropical lower stratosphere. This phenomenon, referred to as "atmospheric tape recorder" has previously been observed for water vapor, CO2, and CO which exhibit an annual cycle. Recently, based on Microwave Limb Sounder (MLS) and the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) satellite measurements, the tape recorder signal has been observed for hydrogen cyanide (HCN) but with an approximately two-year period. Here we report on a model simulation of the HCN tape recorder for the time period 2002-2008 using the Chemical Lagrangian Model of the Stratosphere (CLaMS). The model can reproduce the observed pattern of the HCN tape recorder signal if time-resolved emissions from fires in Indonesia are used as lower boundary condition. This finding indicates that inter-annual variations in biomass burning in Indonesia, which are strongly influenced by El Nino events, control the HCN tape recorder signal. A longer time series of tropical HCN data will probably exhibit an irregular cycle rather than a regular biannual cycle. Citation: Pommrich, R., R. Muller, J.-U. Grooss, G. Gunther, P. Konopka, M. Riese, A. Heil, M. Schultz, H.-C. Pumphrey, and K. A. Walker (2010), What causes the irregular cycle of the atmospheric tape recorder signal in HCN?, Geophys. Res. Lett., 37, L16805, doi:10.1029/2010GL044056

Structural, morphological, magnetic and electrical properties of Ni doped ZnO nanoparticles synthesized by co-precipitation method

Weak ferromagnetic behaviour was obtained in a systematic way at room temperature by doping of ZnO with nickel (Zn1-xNixO, where x = 0.00, 0.05, 0.15 and 0.20). The obtained results were correlated with conductivity and impedance studies. Diamagnetic to ferromagnetic change was observed with increased concentration of nickel. X-ray diffraction analysis confirmed wurtzite ZnO structure of prepared nanopowders while microstrain was increased with nickel concentration. Incorporation of nickel in ZnO structure was confirmed using EDAX analysis, while FTIR spectroscopy provided further information on functional groups. Transmission electron microscopy images showed that the particle sizes are in the range of 12–20 nm, and scanning electron microscopy analyses that grain size decreases with increase in nickel concentration. Photo luminescence studies confirmed the presence of VO and Zni defects in the prepared samples. It was concluded that the defect induced strain, grain boundaries and lower particle sizes are the reasons for weak ferromagnetic behaviour of the investigated samples

Some Aspects of Quantitative Histology of the Liver of A-Jax Mice Before and During Tumor Induction with Carbon Tetrachloride

The proportion of the cell populations composed of parenchymal, littoral, and other types of cells is reported for control mice, mice repeatedly anesthetized, mice fed with olive oil repeatedly, and mice fed with carbon tetrachloride and olive oil, showing that the cellular components undergo a marked change when carbon tetrachloride is administered. The proportion of the liver volume occupied by parenchymal cells is found to be relatively stable throughout the period of tumor induction. The nuclear-cytoplasmic ratio of parenchymal cells is found to fall with the aging of control mice and those fed olive oil or anesthetized during the period of the experiment. The nuclear-cytoplasmic ratio is found to fall to a minimal point during the first two weeks of carbon tetrachloride feeding, thereafter gradually rising to normal values for mice of the same age, and eventually rising, after 24 feedings, to a value exceeding that of normal mice of the same age. Between 24 and 30 feedings the nuclear-cytoplasmic ratio undergoes a decrease. The volumes of parenchymal cell nuclei are found to vary with the position in a lobule, the maximal nuclear volumes being found in a region about 100μ to 200μ from the central vein in lobules of average size

Будівельна лихоманка на Київських схилах

Forty marine-terminating glaciers have been surveyed daily since 2000 using cloud-free MODIS visible imagery (Box and Decker 2011; http://bprc. osu.edu/MODIS/). The net area change of the 40 glaciers during the period of observation has been -1775 km2, with the 18 northernmost (>72°N) glaciers alone contributing to half of the net area change. In 2012, the northernmost glaciers lost a collective area of 255 km2, or 86% of the total net area change of the 40 glaciers surveyed. The six glaciers with the largest net area loss in 2012 were Petermann (-141 km2), 79 glacier (-27 km2), Zachariae (-26 km2), Steenstrup (-19 km2), Steensby (-16 km2, the greatest retreat since observations began), and Jakobshavn (-13 km2). While the total area change was negative in 2012, the area of four of the forty glaciers did increase relative to the end of the 2011 melt season. The anomalous advance of these four glaciers is not easily explained, as the mechanisms controlling the behavior of individual glaciers are uncertain due to their often unique geographic!settings

The 1958–2009 Greenland ice sheet surface melt and the mid-tropospheric atmospheric circulation

peer reviewedaudience: researcherIn order to assess the impact of the mid-tropospheric circulation over the Greenland ice sheet (GrIS) on surface melt, as simulated by the regional climate model MAR, an automatic Circulation type classification (CTC) based on 500 hPa geopotential height from reanalyses is developed. General circulation correlates significantly with the surface melt anomalies for the summers in the period 1958–2009. The record surface melt events observed during the summers of 2007–2009 are linked to the exceptional persistence of atmospheric circulations favouring warm air advection. The CTC emphasizes that summer 500 hPa circulation patterns have changed since the beginning of the 2000s; this process is partly responsible for the recent warming observed over the GrIS

Horizontal transport affecting trace gas seasonality in the Tropical Tropopause Layer (TTL)

We analyze horizontal transport from midlatitudes into the tropics (in-mixing) and its impact on seasonal variations of ozone, carbon monoxide and water vapor in the Tropical Tropopause Layer (TTL). For this purpose, we use three-dimensional backward trajectories, driven by ECMWF ERA-Interim winds, and a conceptual one-dimensional model of the chemical composition of the TTL. We find that the fraction of in-mixed midlatitude air shows an annual cycle with maximum during NH summer, resulting from the superposition of two inversely phased annual cycles for in-mixing from the NH and SH, respectively. In-mixing is driven by the monsoonal upper-level anticyclonic circulations. This circulation pattern is dominated by the Southeast Asian summer monsoon and, correspondingly, in-mixing shows an annual cycle. The impact of in-mixing on TTL mixing ratios depends on the in-mixed fraction of midlatitude air and on the meridional gradient of the particular species. For CO the meridional gradient and consequently the effect of in-mixing is weak. For water vapor, in-mixing effects are negligible. For ozone, the meridional gradient is large and the contribution of in-mixing to the ozone maximum during NH summer is about 50%. This in-mixing contribution is not sensitive to the tropical ascent velocity, which is about 40% too fast in ERA-Interim. As photochemically produced ozone in the TTL shows no distinct summer maximum, the ozone annual anomaly in the upper TTL turns out to be mainly forced by in-mixing of ozone-rich extratropical air during NH summer