scholarly journals Twenty Years of Atmospheric 14Co2 Observations At Schauinsland Station, Germany

Radiocarbon ◽  
1997 ◽  
Vol 39 (2) ◽  
pp. 205-218 ◽  
Author(s):  
Ingeborg Levin ◽  
Bernd Kromer
Keyword(s):  
Northern Hemisphere ◽  
Seasonal Variations ◽  
Fossil Fuel ◽  
Data Sets ◽  
Black Forest ◽  
European Continent ◽  
Northern Latitudes ◽  
Single Exponential Function ◽  
Single Exponential

We present and discuss quasi-continuous long-term 14CO2 observations from the continental background station Schauinsland (48°N, 8°E, 1205 m asl, Black Forest, southern Germany). The observed steady decline of atmospheric 14CO2 from 1977 to 1996 can be described by a single exponential function with an e-folding time of (16.3 ± 0.2) yr. Summer means (May to August) in atmospheric 14CO2 at Schauinsland compare within Δ14C = ±4‰ with measurements made on individual rings from a tree grown in the near vicinity of the Schauinsland site. Both data sets are slightly depleted by up to 5‰ if compared to maritime background measurements of atmospheric 14CO2 made at Izaña, Tenerife. This is due to the influence of fossil fuel CO2 emissions over the European continent as well as generally in mid latitudes of the Northern Hemisphere. δ13C analyses from the Schauinsland samples show mean seasonal variations with an amplitude of ±0.4‰, caused by atmosphere-biosphere exchange, and a mean decrease from 1977 to 1996 of δ13C = −0.017‰ yr−1. This trend is mainly due to an increasing quantity of fossil fuel CO2 in the atmosphere, depleted in 13C/12C ratio, and compares well to trends measured at other stations in mid-to-high northern latitudes.

scholarly journals Mid-Pleistocene transition in glacial cycles explained by declining CO2and regolith removal

2019 ◽  
Vol 5 (4) ◽  
pp. eaav7337 ◽  
Author(s):  
M. Willeit ◽  
A. Ganopolski ◽  
R. Calov ◽  
V. Brovkin
Keyword(s):  
Climate Variability ◽  
Carbon Cycle ◽  
Northern Hemisphere ◽  
Seasonal Variations ◽  
Ice Sheets ◽  
Glacial Cycles ◽  
Solar Insolation ◽  
The Past ◽  
Transient Simulations

Variations in Earth’s orbit pace the glacial-interglacial cycles of the Quaternary, but the mechanisms that transform regional and seasonal variations in solar insolation into glacial-interglacial cycles are still elusive. Here, we present transient simulations of coevolution of climate, ice sheets, and carbon cycle over the past 3 million years. We show that a gradual lowering of atmospheric CO2and regolith removal are essential to reproduce the evolution of climate variability over the Quaternary. The long-term CO2decrease leads to the initiation of Northern Hemisphere glaciation and an increase in the amplitude of glacial-interglacial variations, while the combined effect of CO2decline and regolith removal controls the timing of the transition from a 41,000- to 100,000-year world. Our results suggest that the current CO2concentration is unprecedented over the past 3 million years and that global temperature never exceeded the preindustrial value by more than 2°C during the Quaternary.

scholarly journals Evidence for an earlier greenhouse cooling effect in the stratosphere before 1980 over the Northern Hemisphere

2014 ◽  
Vol 14 (15) ◽  
pp. 7705-7720 ◽  
Author(s):  
C. S. Zerefos ◽  
K. Tourpali ◽  
P. Zanis ◽  
K. Eleftheratos ◽  
C. Repapis ◽  
...  
Keyword(s):  
Global Warming ◽  
Northern Hemisphere ◽  
Geopotential Height ◽  
Lower Stratosphere ◽  
Lower Troposphere ◽  
Radiosonde Data ◽  
Data Sets ◽  
Radiative Processes ◽  
Before And After

Abstract. This study provides a new look at the observed and calculated long-term temperature changes from the lower troposphere to the lower stratosphere since 1958 over the Northern Hemisphere. The data sets include the NCEP/NCAR reanalysis, the Free University of Berlin (FU-Berlin) and the RICH radiosonde data sets as well as historical simulations with the CESM1-WACCM global model participating in CMIP5. The analysis is mainly based on monthly layer mean temperatures derived from geopotential height thicknesses in order to take advantage of the use of the independent FU-Berlin stratospheric data set of geopotential height data since 1957. This approach was followed to extend the records for the investigation of the stratospheric temperature trends to the earliest possible time. After removing the natural variability with an autoregressive multiple regression model our analysis shows that the period 1958–2011 can be divided into two distinct sub-periods of long-term temperature variability and trends: before and after 1980. By calculating trends for the summer time to reduce interannual variability, the two periods are as follows. From 1958 until 1979, a non-significant trend (0.06 ± 0.06 °C decade−1 for NCEP) and slightly cooling trends (−0.12 ± 0.06 °C decade−1 for RICH) are found in the lower troposphere. The second period from 1980 to the end of the records shows significant warming (0.25 ± 0.05 °C decade−1 for both NCEP and RICH). Above the tropopause a significant cooling trend is clearly seen in the lower stratosphere both in the pre-1980 period (−0.58 ± 0.17 °C decade−1 for NCEP, −0.30 ± 0.16 °C decade−1 for RICH and −0.48 ± 0.20 °C decade−1 for FU-Berlin) and the post-1980 period (−0.79 ± 0.18 °C decade−1 for NCEP, −0.66 ± 0.16 °C decade−1 for RICH and −0.82 ± 0.19 °C decade−1 for FU-Berlin). The cooling in the lower stratosphere persists throughout the year from the tropics up to 60° N. At polar latitudes competing dynamical and radiative processes reduce the statistical significance of these trends. Model results are in line with reanalysis and the observations, indicating a persistent cooling (−0.33 °C decade−1) in the lower stratosphere during summer before and after 1980; a feature that is also seen throughout the year. However, the lower stratosphere CESM1-WACCM modelled trends are generally lower than reanalysis and the observations. The contrasting effects of ozone depletion at polar latitudes in winter/spring and the anticipated strengthening of the Brewer–Dobson circulation from man-made global warming at polar latitudes are discussed. Our results provide additional evidence for an early greenhouse cooling signal in the lower stratosphere before 1980, which appears well in advance relative to the tropospheric greenhouse warming signal. The suitability of early warning signals in the stratosphere relative to the troposphere is supported by the fact that the stratosphere is less sensitive to changes due to cloudiness, humidity and man-made aerosols. Our analysis also indicates that the relative contribution of the lower stratosphere versus the upper troposphere low-frequency variability is important for understanding the added value of the long-term tropopause variability related to human-induced global warming.

scholarly journals In vivo instability of red-blood-cell-bound C3d and C4d

Blood ◽  
1983 ◽  
Vol 62 (5) ◽  
pp. 965-971 ◽  
Author(s):  
H Jr Chaplin ◽  
ME Coleman ◽  
MC Monroe
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Normal Subjects ◽  
The Third ◽  
Antigen 85 ◽  
Single Exponential Function ◽  
Single Exponential

Until now, there have been no measurements of the in vivo stability of red-blood-cell-bound C3d and C4d subfragments of the third and fourth components of human complement. We have recently described a radiolabeled antiantiglobulin method for measuring RBC-bound C3d and have demonstrated that small amounts of C3d are present on RBC of all normal subjects tested. In the present study, the method was applied to follow the increments above baseline of RBC-bound C3d and C4d produced by autotransfusing 3 normal volunteers with 160–200 ml of RBC strongly coated in vitro by C3d and C4d. Posttransfusion measurements were carried out over 21–34 days. Immediate and long-term in vivo survival of the transfused RBC was unimpaired by C3d and C4d coating. Of the bound C3d antigen, 85%–95% disappeared from circulating RBC in 5–8 days; the remainder disappeared more slowly, with half-times in the range of 8–29 days. C4d antigen disappeared substantially more slowly, describable by a single exponential function in 2 of the 3 subjects, with half-times in the range of 12–31 days. Recognition of the in vivo instability of RBC-bound C3d helps in interpreting steady-state and changing levels of RBC C3d coating in a variety of alloimmune and autoimmune disorders.

scholarly journals Variability of southwest monsoon rainfall over West Bengal

MAUSAM ◽  
2022 ◽  
Vol 44 (4) ◽  
pp. 353-358
Author(s):  
B. BISWAS ◽  
K. GUPTA
Keyword(s):  
Seasonal Variations ◽  
West Bengal ◽  
Monsoon Rainfall ◽  
Southwest Monsoon ◽  
Seasonal Rainfall ◽  
Northern Latitudes ◽  
Rainfall Trends ◽  
Latitudinal Variations ◽  
Southwest Monsoon Rainfall

Monthly and seasonal variations of southwest monsoon rainfall over the districts of Gangetic and Sub-Himalayan West Bengal are presented and their differences discussed. Latitudinal variations of monsoon rainfall are brought out. Decadal means of seasonal rainfall over plains are compared with those at higher elevations and northern latitudes. An attempt is made to study long term rainfall trends.

scholarly journals In vivo instability of red-blood-cell-bound C3d and C4d

Blood ◽  
1983 ◽  
Vol 62 (5) ◽  
pp. 965-971 ◽  
Author(s):  
H Jr Chaplin ◽  
ME Coleman ◽  
MC Monroe
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Normal Subjects ◽  
The Third ◽  
Antigen 85 ◽  
Single Exponential Function ◽  
Single Exponential

Abstract Until now, there have been no measurements of the in vivo stability of red-blood-cell-bound C3d and C4d subfragments of the third and fourth components of human complement. We have recently described a radiolabeled antiantiglobulin method for measuring RBC-bound C3d and have demonstrated that small amounts of C3d are present on RBC of all normal subjects tested. In the present study, the method was applied to follow the increments above baseline of RBC-bound C3d and C4d produced by autotransfusing 3 normal volunteers with 160–200 ml of RBC strongly coated in vitro by C3d and C4d. Posttransfusion measurements were carried out over 21–34 days. Immediate and long-term in vivo survival of the transfused RBC was unimpaired by C3d and C4d coating. Of the bound C3d antigen, 85%–95% disappeared from circulating RBC in 5–8 days; the remainder disappeared more slowly, with half-times in the range of 8–29 days. C4d antigen disappeared substantially more slowly, describable by a single exponential function in 2 of the 3 subjects, with half-times in the range of 12–31 days. Recognition of the in vivo instability of RBC-bound C3d helps in interpreting steady-state and changing levels of RBC C3d coating in a variety of alloimmune and autoimmune disorders.

scholarly journals Nocturnal Sporadic-E Activity at Two Southern Hemisphere Stations over Three Solar Cycles

1984 ◽  
Vol 37 (2) ◽  
pp. 231
Author(s):  
WJ Baggaley
Keyword(s):  
Southern Hemisphere ◽  
Sunspot Number ◽  
High Latitude ◽  
Seasonal Variations ◽  
Data Sets ◽  
Solar Cycles ◽  
Geomagnetic Index ◽  
Sporadic E ◽  
Long Term Variations

Analyses are presented of monthly values of the occurrence of the ionospheric parameters j~ E; and foE; for the South Pacific stations Christchurch and Rarotonga over three complete solar cycles. For each station both pre-midnight and post-midnight data show seasonal variations similar to daytime with the high latitude station showing a winter enhancement. Data fluctuations of scales longer than a year are very pronounced compared with variations in other ionospheric parameters. No correlations exist between any of the data sets and either the sunspot number Rz or geomagnetic index. Long-term variations in fi.E, and fo E; are uncorrelated at a particular station.

scholarly journals The Climate of the Common Era off the Iberian Peninsula

2017 ◽  
Author(s):  
Fátima Abrantes ◽  
Teresa Rodrigues ◽  
Marta Rufino ◽  
Emília Salgueiro ◽  
Dulce Oliveira ◽  
...  
Keyword(s):  
Iberian Peninsula ◽  
Northern Hemisphere ◽  
North Atlantic ◽  
Ice Age ◽  
Higher Plant ◽  
European Continent ◽  
Climate Conditions ◽  
Shelf Sediment ◽  
South Portugal

Abstract. The Iberian Peninsula, at North Atlantic mid-latitude and the western extreme of the European continent, is a relevant area for climate reconstructions. This work provides multi-proxy records measured in 7 inner-shelf sediment sequences from 5 sites located between South Portugal (Algarve) and Northwest Spain (Galiza) (36 to 42º N) and targets a regional reconstruction of climate variability during the last 2000 yr. Alkenone derived Sea Surface Temperature (SST) reconstructions were compared to on-land precipitation given by higher plant n-alkanes and pollen data, to assess the relationship between hydroclimate (drought and/or precipitation) and oceanic SST. The SST records reveal a long-term scale cooling (±1 ºC/2000 yr) that ends at the beginning of the 20th century at all sites. This cooling is a follow up of the cooling process started after the Holocene optimum and driven by a decrease in summer insolation in the Northern Hemisphere. A multi-decadal/ centennial variability is detected within this long-term cooling in convergence with other records from Spain, Europe and the Northern Hemisphere. Warm SST conditions prevailed throughout the first 1300 yr, encompassing the Roman Period (RP), the Dark Ages (DA) and the Medieval Warm Period (MWP). A cooling initiated at 1300 CE, led to 4 centuries of ±1 ºC colder mean SSTs contemporary with the Little Ice Age (LIA). The transition towards the Industrial Era starts by 1800 CE with a SST rise to pre-LIA levels. Particular climate conditions have been detected in Western Iberian margin records and reveal two distinct phases within the MWP and a two-step SST increase towards the Industrial Era. The intense precipitation/flooding and warm winters but cooler intermediate seasons (spring and fall) observed for the early MWP imply the interplay of internal oceanic variability with the three atmospheric circulation modes, North Atlantic Oscillation (NAO), East Atlantic (EA) and Sandinavia (SCAND) in a positive phase. The late MWP, marked by drier and cooler winters and warmer intermediate seasons calls for a change in sign of the SCAND. A stronger mark of oceanic influences on Western Iberian Peninsula starts with the transition to the Industrial Era.

Asian Americans and Pacific Islanders: Employment Issues in the United States

2011 ◽  
Vol 9 (1-2) ◽  
pp. 58-69
Author(s):  
Marlene Kim
Keyword(s):  
United States ◽  
Asian Americans ◽  
The United States ◽  
Current Data ◽  
Pacific Islanders ◽  
Native Hawaiians ◽  
Data Sets ◽  
High Poverty ◽  
Unemployment Rates

Asian Americans and Pacific Islanders (AAPIs) in the United States face problems of discrimination, the glass ceiling, and very high long-term unemployment rates. As a diverse population, although some Asian Americans are more successful than average, others, like those from Southeast Asia and Native Hawaiians and Pacific Islanders (NHPIs), work in low-paying jobs and suffer from high poverty rates, high unemployment rates, and low earnings. Collecting more detailed and additional data from employers, oversampling AAPIs in current data sets, making administrative data available to researchers, providing more resources for research on AAPIs, and enforcing nondiscrimination laws and affirmative action mandates would assist this population.

Raids and Retaliation

2017 ◽  
Author(s):  
Tom Scott
Keyword(s):  
Black Forest

The Swiss mounted raids across the Hochrhein and the Alpine Rhine, as well as taking possession of the bishop of Konstanz’s castles. The Swabian League responded with sorties south of the Rhine. These raids were mostly for booty and were followed by rapid withdrawal: there was no obvious strategic purpose behind them. Both sides employed mercenaries. It is doubtful whether the Swiss had any long-term intention of seizing the southern Black Forest or the Hegau, though military access to the four Austrian ‘Forest Towns’ was an important aim. Nevertheless, individually Zürich and Schaffhausen had territorial ambitions in the Klettgau and Hegau, respectively.

Epidemiological Evidence that Maternal Influenza Contributes to the Aetiology of Schizophrenia

1993 ◽  
Vol 163 (4) ◽  
pp. 522-534 ◽  
Author(s):  
W. Adams ◽  
R. E. Kendell ◽  
E. H. Hare ◽  
P. Munk-Jørgensen
Keyword(s):  
Data Sets ◽  
Time Lags ◽  
Epidemiological Evidence ◽  
Intrauterine Development ◽  
Increased Risk ◽  
Schizophrenic Patients ◽  
The Relationship ◽  
Monthly Incidence ◽  
Maternal Influenza

The epidemiological evidence that the offspring of women exposed to influenza in pregnancy are at increased risk of schizophrenia is conflicting. In an attempt to clarify the issue we explored the relationship between the monthly incidence of influenza (and measles) in the general population and the distribution of birth dates of three large series of schizophrenic patients - 16 960 Scottish patients born in 1932–60; 22 021 English patients born in 1921–60; and 18 723 Danish patients born in 1911–65. Exposure to the 1957 epidemic of A2 influenza in midpregnancy was associated with an increased incidence of schizophrenia, at least in females, in all three data sets. We also confirmed the previous report of a statistically significant long-term relationship between patients' birth dates and outbreaks of influenza in the English series, with time lags of - 2 and - 3 months (the sixth and seventh months of pregnancy). Despite several other negative studies by ourselves and others we conclude that these relationships are probably both genuine and causal; and that maternal influenza during the middle third of intrauterine development, or something closely associated with it, is implicated in the aetiology of some cases of schizophrenia.

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