Man and his physical environment: Gary D. McKenzie and Russell O. Utgard (Editors): Readings in Environmental Geology. Burgess Publishing Company,Minneapolis. 338 pp. Price $4.95     

Edward D Goldberg 《Geochimica et cosmochimica acta》1973,37(1):171

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Coronal electron density maps for 7 March, 1970, derived from Mgx λ625 spectroheliograms     

G. L. Withbroe  A. K. Dupree  L. Goldberg  M. C. E. Huber  R. W. Noyes  W. H. Parkinson  E. M. Reeves 《Solar physics》1971,21(2):272-280

We have analyzed daily Mgx 625 spectroheliograms acquired by the Harvard College Observatory experiment on OSO-6 for a 28-day period centered on 7 March, 1970, the date of a well-observed total solar eclipse. These data are used to construct maps of the variation across the solar disk of the electron density at the base of the corona. The correspondence of high and low density regions with regions of enhanced and reduced emission in white light and Mgx pictures made during or near the time of the eclipse are described.  相似文献   

Climate change, ambient ozone, and health in 50 US cities   总被引：2，自引：1，他引：2  

Michelle L. Bell  Richard Goldberg  Christian Hogrefe  Patrick L. Kinney  Kim Knowlton  Barry Lynn  Joyce Rosenthal  Cynthia Rosenzweig  Jonathan A. Patz 《Climatic change》2007,82(1-2):61-76

We investigated how climate change could affect ambient ozone concentrations and the subsequent human health impacts. Hourly concentrations were estimated for 50 eastern US cities for five representative summers each in the 1990s and 2050s, reflecting current and projected future climates, respectively. Estimates of future concentrations were based on the IPCC A2 scenario using global climate, regional climate, and regional air quality models. This work does not explore the effects of future changes in anthropogenic emissions, but isolates the impact of altered climate on ozone and health. The cities’ ozone levels are estimated to increase under predicted future climatic conditions, with the largest increases in cities with present-day high pollution. On average across the 50 cities, the summertime daily 1-h maximum increased 4.8 ppb, with the largest increase at 9.6 ppb. The average number of days/summer exceeding the 8-h regulatory standard increased 68%. Elevated ozone levels correspond to approximately a 0.11% to 0.27% increase in daily total mortality. While actual future ozone concentrations depend on climate and other influences such as changes in emissions of anthropogenic precursors, the results presented here indicate that with other factors constant, climate change could detrimentally affect air quality and thereby harm human health.  相似文献   

Anomalous strontium and lead isotope signatures in the off-rift Öræfajökull central volcano in south-east Iceland: Evidence for enriched endmember(s) of the Iceland mantle plume?     

Tore Prestvik  Steven Goldberg  Haraldur Karlsson  Karl Grnvold 《Earth and Planetary Science Letters》2001,190(3-4):211-220

The currently active off-rift central volcano Öræfajökull in south-east Iceland sits unconformably on much older (10–12 Ma) and eroded crust. The composition of recent volcanics ranges from basalt to rhyolite, but the series is more sodic alkaline than the common rift zone tholeiitic suites. In this study we present Sr, Nd, Pb and O isotopic data for a suite of Öræfajökull samples. The complete suite shows typical mantle values for oxygen isotopes. The ⁸⁷Sr/⁸⁶Sr ratios (average of 15 SAMPLES=0.703702) of the modern Öræfajökull rocks (basalts as well as rhyolites) are much higher than observed so far for any other Icelandic rocks. The ¹⁴³Nd/¹⁴⁴Nd ratios (average=0.512947; n=15) are lower than for rift rocks, but similar to rocks of the off-rift Snæfellsnes volcanic zone. Furthermore, the Öræfajökull rocks are enriched in the ²⁰⁷Pb/²⁰⁴Pb and ²⁰⁸Pb/²⁰⁴Pb isotope ratios compared to Icelandic rift basalts. The enriched nature of the suite indicates that Öræfajökull samples a source component that has characteristics common with EM2 type mantle. Furthermore, it is concluded that the silicic rocks of Öræfajökull formed by fractional crystallization from mafic melts rather than by partial melting of older crust.  相似文献   

Petrophysical characterization and natural fracturing in an olivine-dolerite aquifer     

Katharine Burgdorff  Dave Goldberg 《Visual Geosciences》2001,6(3):1-28

As part of a study investigating the naturally-occurring fractures in mafic rocks, two holes were drilled 450 m apart through the Palisades dolerite sill in New York. Well-2 is 229 m deep and Well-3 was drilled to 305 m, both penetrating through the sill and into the underlying Triassic sediments of the Newark Basin. Both holes were logged with downhole geophysical tools, including the BHTV, which acoustically images fractures intersecting the well. Understanding the fracture pattern, density, and porosity in the sill is essential for identifying possible zones of active fluid flow and high permeability. Using the BHTV logs, 96 and 203 fractures were digitally mapped within the sill in Well-2 and Well-3, respectively. Most fractures appear to dip steeply (76-78°). There is a shift in fracture orientation, however, and these fractures may or may not be continuous over the short lateral distance between Well-2 and Well-3. The lithology of the sill as identified by drill chips is nevertheless continuous between the holes. Both intersect a 7 m thick olivine-rich layer about 15 m above the bottom of the sill. Several fractures identified in Well-2 have large apparent aperture (>6cm) which correspond to high porosity zones (6-14%) observed in the logs. Resistivity logs were used to compute porosity using Archie's law and match well with the neutron porosity log in Well-2. We use the relationship between porosity and fracture aperture within the sill at Well-2 to infer the porosity in Well-3. High-porosity, large-aperture zones, including the target olivine layer, are identified in both holes. Changes in the temperature gradient log indicate active fluid flow in the sill, although flow appears to be most active in the sediments. Direct field measurements of bulk permeability, hydrologic modeling of fluid flow and calibration of fracture and log porosity will be undertaken in the future.  相似文献   

The effect of changes in daily and interannual climatic variability on CERES-Wheat: A sensitivity study   总被引：4，自引：1，他引：4  

Linda O. Mearns  Cynthia Rosenzweig  Richard Goldberg 《Climatic change》1996,32(3):257-292

We investigate the effect of changes in daily and interannual variability of temperature and precipitation on yields simulated by the CERES-Wheat model at two locations in the central Great Plains. Changes in variability were effected by adjusting parameters of the Richardson daily weather generator. Two types of changes in precipitation were created: one with both intensity and frequency changed; and another with change only in persistence. In both types mean total monthly precipitation is held constant. Changes in daily (and interannual) variability of temperature result in substantial changes in the mean and variability of simulated wheat yields. With a doubling of temperature variability, large reductions in mean yield and increases in variability of yield result primarily from crop failures due to winter kill at both locations. Reduced temperature variability has little effect. Changes in daily precipitation variability also resulted in substantial changes in mean and variability of yield. Interesting interactions of the precipitation variability changes with the contrasting base climates are found at the two locations. At one site where soil moisture is not limiting, mean yield decreased and variability of yield increased with increasing precipitation variability, whereas mean yields increased at the other location, where soil moisture is limiting. Yield changes were similar for the two different types of precipitation variability change investigated. Compared to an earlier study for the same locations wherein variability changes were effected by altering observed time series, and the focus was on interannual variability, the present results for yield changes are much more substantial. This study demonstrates the importance of taking into account change in daily (and interannual) variability of climate when analyzing the effect of climate change on crop yields.The National Center for Atmospheric Research is sponsored by the National Science Foundation.  相似文献   

The decade-resolved record of the response of East Siberia to abrupt climatic changes in the North Atlantic over the last glacial-interglacial cycle     

E. L. Goldberg  M. A. Phedorin  E. P. Chebykin  O. M. Khlystov  N. A. Zhuchenko 《Doklady Earth Sciences》2008,421(2):961-964

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Galaxy candidates in the Zone of Avoidance     

Ofer Lahav  Noah Brosch  Evgeny Goldberg  George K. T. Hau  Renée C. Kraan-Korteweg  & Andy J. Loan 《Monthly notices of the Royal Astronomical Society》1998,299(1):24-30

Motivated by recent discoveries of nearby galaxies in the Zone of Avoidance (ZOA), we conducted a pilot study of galaxy candidates at low galactic latitude, near galactic longitude l  ∼ 135°, where the Supergalactic plane is crossed by the Galactic plane. We observed with the 1-m Wise Observatory in the l band 17 of the 'promising' candidates identified by visual examination of Palomar red plates by Hau et al. A few candidates were also observed in R or B bands, or had spectroscopic observations performed at the Isaac Newton Telescope and at the Wise Observatory. Our study suggests that there are probably 10 galaxies in this sample. We also identify a probable planetary nebula. The final confirmation of the nature of these sources must await the availability of full spectroscopic information. The success rate of ∼ 50 per cent in identifying galaxies at galactic latitude | b | < 5° indicates that the ZOA is a promising region to discover new galaxies.  相似文献   

Potential Effects of Global Warming on Waterfowl Populations Breeding in the Northern Great Plains   总被引：4，自引：0，他引：4  

Lisa G. Sorenson  Richard Goldberg  Terry L. Root  Michael G. Anderson 《Climatic change》1998,40(2):343-369

The Prairie Pothole Region (PPR) of the Northern Great Plains is the most important breeding area for waterfowl in North America. Historically, the size of breeding duck populations in the PPR has been highly correlated with spring wetland conditions. We show that one indicator of climate conditions, the Palmer Drought Severity Index (PDSI), is strongly correlated with annual counts (from 1955 to 1996) of both May ponds (R2 = 0.72, p < 0.0001) and breeding duck populations (R2 = 0.69, p < 0.0001) in the Northcentral U.S., suggesting the utility of PDSI as an index for climatic factors important to wetlands and ducks. We then use this relationship to project future pond and duck numbers based on PDSI values generated from sensitivity analyses and two general circulation model (GCM) scenarios. We investigate the sensitivity of PDSI to fixed changes in temperature of 0°C, +1.5°C, +2.5°C, and +4.0°C in combination with fixed changes in precipitation of -10%, +0%, +7%, and +15%, changes spanning the range of typically-projected values for this region from human-induced climatic change. Most (11 of 12) increased temperature scenarios tested result in increased drought (due to greater evapotranspiration under warmer temperatures) and declining numbers of both wetlands and ducks. Assuming a doubling of CO2 by 2060, both the equilibrium and transient GCM scenarios we use suggest a major increase in drought conditions. Under these scenarios, Northcentral U.S. breeding duck populations would fluctuate around means of 2.1 or 2.7 million ducks based on the two GCMs, respectively, instead of the present long-term mean of 5.0 million. May pond numbers would fluctuate around means of 0.6 or 0.8 million ponds instead of the present mean of 1.3 million. The results suggest that the ecologically and economically important PPR could be significantly damaged by climate changes typically projected. We make several recommendations for policy and research to help mitigate potential effects.  相似文献   

Millennium scale environment changes of the Okhotsk Sea during last 80 kyr and their phase relationship with global climate changes     

Sergey Alexandrovich Gorbarenko  Evgenia L’vovich Goldberg  Michaele Kashgarian  Tat’yana Alekseevna Velivetskaya  Sergey Petrovich Zakharkov  Vladimir Stepanovich Pechnikov  Alexandr Anatol’evich Bosin  Olga Yur’evna Psheneva  Elena Diamilevna Ivanova 《Journal of Oceanography》2007,63(4):609-623

The paper presents the records of several paleoproductivity proxies (PP) (biogenic opal and Ba (Si_bio, Ba_bio), organic carbon (C_org) and carbonate Ca_carb, chlorin and benthic foraminifera abundance (BFA)) in sediments of the Okhotsk Sea for the last 80 kyr with a resolution of ∼100–300 years. The sediment age model was based on the AMS ¹⁴C data, records of benthic foraminifera δ¹⁸O, paleointensity of the Earth’s geomagnetic field and magnetic susceptibility. PP values demonstrate series of severe prolonged productivity drops in the Okhotsk Sea followed by a sharp increase during the last glaciation. On the basis of quantitative estimations of the paleoproductivity in the Okhotsk Sea during the cold MIS 2 and warm Holocene (Gorbarenko and Goldberg, 2005), it is suggested that the millennium scale relationship in productivity-climate changes of this basin was similar: an increase in the sea’s productivity was related with regional climate warming and vice-versa. The PP records of productivity/climate oscillations in the Okhotsk Sea during MIS 2–4 occurred contemporaneously with the North Atlantic cold Heinrich events (HE) and Greenland Dansgaard-Oyeshger interstadial (DOI). Observed successions of prolonged climate cooling events followed by rapid, abrupt warming are similar to climate and environmental oscillations in the N. Atlantic and Greenland, that confirms the millennium-scale climate changes synchronicities in the Northern Hemisphere including the far NW Pacific, the hydrology and climate conditions of which are close to those of the Okhotsk Sea. Synchronism of the N. Hemisphere severe cooling (including the Okhotsk Sea) with the Antarctic warming suggests that mechanisms of the “seesaw” effect (Blunier and Brook, 2001) in the low latitude heat redistribution between high latitudes of both hemispheres were more complicated than direct NADW formation forcing and encompasses the global atmospheric reorganization. Within the PP used a closer connection in the Okhotsk Sea millennium oscillations was observed for the C_org, BFA and chlorin; Ba_bio increases more closely to DOI. Si_bio variability does not show any evident correlation with productivity changes.  相似文献