Enhanced Seasonal Exchange of CO2 by Northern Ecosystems Since 1960

Science ◽  
2013 ◽  
Vol 341 (6150) ◽  
pp. 1085-1089 ◽  
Author(s):  
H. D. Graven ◽  
R. F. Keeling ◽  
S. C. Piper ◽  
P. K. Patra ◽  
B. B. Stephens ◽  
...  
Keyword(s):  
Boreal Forests ◽  
Atmospheric Carbon Dioxide ◽  
Ecosystem Models ◽  
The North ◽  
Ecological Changes ◽  
Term Change ◽  
Major Shift ◽  
Underlying Mechanisms ◽  
Global Carbon

Seasonal variations of atmospheric carbon dioxide (CO2) in the Northern Hemisphere have increased since the 1950s, but sparse observations have prevented a clear assessment of the patterns of long-term change and the underlying mechanisms. We compare recent aircraft-based observations of CO2 above the North Pacific and Arctic Oceans to earlier data from 1958 to 1961 and find that the seasonal amplitude at altitudes of 3 to 6 km increased by 50% for 45° to 90°N but by less than 25% for 10° to 45°N. An increase of 30 to 60% in the seasonal exchange of CO2 by northern extratropical land ecosystems, focused on boreal forests, is implicated, substantially more than simulated by current land ecosystem models. The observations appear to signal large ecological changes in northern forests and a major shift in the global carbon cycle.

The Sydney Cyprus Survey Project: An Interdisciplinary Investigation of Long-Term Change in the North Central Troodos, Cyprus

1999 ◽  
Vol 26 (1) ◽  
pp. 19 ◽  
Author(s):  
Michael Given ◽  
A. Bernard Knapp ◽  
Nathan Meyer ◽  
Timothy E. Gregory ◽  
Vasiliki Kassianidou ◽  
...  
Keyword(s):  
North Central ◽  
The North ◽  
Term Change

Increasing anthropogenic nitrogen in the North Pacific Ocean

Science ◽  
2014 ◽  
Vol 346 (6213) ◽  
pp. 1102-1106 ◽  
Author(s):  
Il-Nam Kim ◽  
Kitack Lee ◽  
Nicolas Gruber ◽  
David M. Karl ◽  
John L. Bullister ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
North Pacific ◽  
North Pacific Ocean ◽  
Limited Region ◽  
The North ◽  
Term Change ◽  
Rate Of Increase ◽  
Anthropogenic Nitrogen ◽  
The North Pacific

The recent increase in anthropogenic emissions of reactive nitrogen from northeastern Asia and the subsequent enhanced deposition over the extensive regions of the North Pacific Ocean (NPO) have led to a detectable increase in the nitrate (N) concentration of the upper ocean. The rate of increase of excess N relative to phosphate (P) was found to be highest (∼0.24 micromoles per kilogram per year) in the vicinity of the Asian source continent, with rates decreasing eastward across the NPO, consistent with the magnitude and distribution of atmospheric nitrogen deposition. This anthropogenically driven increase in the N content of the upper NPO may enhance primary production in this N-limited region, potentially leading to a long-term change of the NPO from being N-limited to P-limited.

scholarly journals Long-term continuous atmospheric CO<sub>2</sub> measurements at Baring Head, New Zealand

2012 ◽  
Vol 5 (12) ◽  
pp. 3109-3117 ◽  
Author(s):  
G. W. Brailsford ◽  
B. B. Stephens ◽  
A. J. Gomez ◽  
K. Riedel ◽  
S. E. Mikaloff Fletcher ◽  
...  
Keyword(s):  
New Zealand ◽  
Atmospheric Carbon Dioxide ◽  
Air Masses ◽  
The North ◽  
Low Co2 ◽  
Ocean Region ◽  
Carbon Dioxide Co2 ◽  
Instrumental Precision

Abstract. We present descriptions of the in situ instrumentation, calibration procedures, intercomparison efforts, and data filtering methods used in a 39-yr record of continuous atmospheric carbon dioxide (CO2) observations made at Baring Head, New Zealand. Located on the southern coast of the North Island, Baring Head is exposed to extended periods of strong air flow from the south with minimal terrestrial influence resulting in low CO2 variability. The site is therefore well suited for sampling air masses that are representative of the Southern Ocean region. Instrumental precision is better than 0.015 ppm (1-σ) on 1-Hz values. Comparisons to over 600 co-located flask samples, as well as laboratory based flask and cylinder comparison exercises, suggest that over recent decades compatibility with respect to the Scripps Institution of Oceanography (SIO) and World Meteorological Organisation (WMO) CO2 scales has been 0.3 ppm or better.

scholarly journals Distribution and Diversity of Beauveria in Boreal Forests of Northern European Russia

2021 ◽  
Vol 9 (7) ◽  
pp. 1409
Author(s):  
Igor A. Kazartsev ◽  
Georgy R. Lednev
Keyword(s):  
Boreal Forests ◽  
Random Distribution ◽  
European Russia ◽  
Molecular Evidence ◽  
The North ◽  
Northern European ◽  
Northern Areas ◽  
Northern European Russia ◽  
Long Term Survey

The distribution and genetic diversity of 91 of Beauveria isolates collected during a long-term survey in boreal forests of northern European Russia was studied. Based on morphological and sequence analysis of TEF and Bloc loci, three Beauveria spp. were identified: B. pseudobassiana, B. bassiana, and B. caledonica, with abundance of 81, 11, and 8%, respectively. Through multilocus sequencing, four haplotypes of B. bassiana and two haplotypes of B. caledonica were detected. Twelve haplotypes of B. pseudobassiana with non-random distribution were identified. Two haplotypes of B. pseudobassiana were the most abundant and widespread occurring across the whole study area, whereas others tended to be more specific to either the north or south of the study area, indicating the presence of different subpopulations. For further analysis of these putative subpopulations, southern and northern areas were separated along the boundary of the Köppen–Geiger climate zones (dfb and dfc), and the genetic structure was examined by analysis of molecular variance and spatial autocorrelation. Molecular evidence of intraspecific recombination of B. pseudobassiana and B. bassiana across northern European Russia area was indicated.

scholarly journals CARINA-Oxygen: a new high-quality oxygen database for the Atlantic Ocean

2009 ◽  
Vol 2 (1) ◽  
pp. 103-135 ◽  
Author(s):  
I. Stendardo ◽  
N. Gruber ◽  
A. Körtzinger
Keyword(s):  
Data Base ◽  
North Atlantic ◽  
Deep Ocean ◽  
Atlantic Region ◽  
The North ◽  
Term Change ◽  
Sample Density ◽  
The Individual ◽  
Oxygen Measurements

Abstract. In the CARINA project, a new dataset with many previously unpublished hydrographic data from the Atlantic, Arctic and Southern Ocean was assembled and subjected to careful quality control (QC) procedures. In this paper, we present the dissolved oxygen measurements in the Atlantic region of the database and describe in detail the secondary QC procedures that aim to ensure optimal consistency between different cruises in order to permit studies of long-term change. The secondary QC is based on a cross-over analysis, i.e. the comparison of deep ocean data at places that were sampled by different cruises at different times. Initial adjustments to the individual cruises were then determined by an inverse procedure that computes a set of adjustments that requires the minimum amount of adjustment and at the same time reduces the offsets in an optimal manner. The initial adjustments were then reviewed by the CARINA members, and only those that passed the following two criteria were adopted: (i) the region not subject to substantial temporal variability, and (ii) the adjustment must be based on at least three stations from each cruise. No adjustment was recommended for cruises that did not fit these criteria. The final CARINA-Oxygen database has 113005 oxygen samples from 9535 stations obtained during 98 cruises covering three decades. The sampling density of the oxygen data is particularly good in the North Atlantic north of about 40° N especially after 1987. In contrast, the sample density in the South Atlantic is much lower. Some cruises appear to have poor data quality, and were subsequently omitted from the adjusted data base. Of the data included in the adjusted data base, 20% were adjusted with a mean adjustment of 2%.

The Sydney Cyprus Survey Project: An Interdisciplinary Investigation of Long-Term Change in the North Central Troodos, Cyprus

1999 ◽  
Vol 26 (1) ◽  
pp. 19-39 ◽  
Author(s):  
Michael Given ◽  
A. Bernard Knapp ◽  
Nathan Meyer ◽  
Timothy E. Gregory ◽  
Vasiliki Kassianidou ◽  
...  
Keyword(s):  
North Central ◽  
The North ◽  
Term Change

scholarly journals Long-term continuous atmospheric CO<sub>2</sub> measurements at Baring Head, New Zealand

2012 ◽  
Vol 5 (4) ◽  
pp. 5889-5912 ◽  
Author(s):  
G. W. Brailsford ◽  
B. B. Stephens ◽  
A. J. Gomez ◽  
K. Riedel ◽  
S. E. Mikaloff Fletcher ◽  
...  
Keyword(s):  
New Zealand ◽  
Atmospheric Carbon Dioxide ◽  
Air Masses ◽  
The North ◽  
Low Co2 ◽  
Ocean Region ◽  
Carbon Dioxide Co2 ◽  
Instrumental Precision

Abstract. We present a 39-yr record of continuous atmospheric carbon dioxide (CO2) observations made at Baring Head, New Zealand using a succession of infrared analyser instruments. We include descriptions of the in situ instrumentation, calibration procedures, intercomparison efforts, and data-filtering methods. Located on the southern coast of the North Island, Baring Head is exposed to extended periods of strong air flow from the south with minimal terrestrial influence resulting in low CO2 variability. The site is therefore well suited for sampling air masses that are representative of the Southern Ocean region. Instrumental precision is better than 0.015 ppm (1-σ) on 1-Hz values and comparisons to over 600 co-located flask samples, as well as laboratory based flask and cylinder comparison exercises, suggests that over recent decades compatibility with respect to the Scripps Institute of Oceanography (SIO) and World Meteorological Organisation (WMO) CO2 scales has been 0.3 ppm or better.

Preface

1995 ◽  
Vol 348 (1324) ◽  
pp. 123-124 ◽  
Keyword(s):  
Carbon Dioxide ◽  
North Atlantic ◽  
Atmospheric Carbon Dioxide ◽  
Global Climate ◽  
The North ◽  
Considerable Controversy ◽  
The North Atlantic ◽  
Oceanic Carbon ◽  
The Impact

The oceans and the atmosphere are intimately linked in determining global climate. The greenhouse gas carbon dioxide is a key player in this, its concentration in the atmosphere being dynamically controlled via generation from the biosphere, geosphere and hydrosphere, and through ‘draw down’ into carbon reservoirs of short-term historical and long-term geological timescales. Physical and biological processes in the oceans play a central role in atmospheric carbon dioxide regulation. Hence, public concern over climate change immediately confronts our knowledge of the oceanic carbon cycle, both now and in the past. The North Atlantic is of special interest, being an extremely dynamic ocean with an enormous effect on the heat and humidity balance of the Northern Hemisphere and, in consequence, on the agriculture and lifestyles of the populations of North America, Europe and Asia. There is considerable controversy over the role of the North Atlantic in drawing down man-made CO 2 from the atmosphere and hence in determining climate. Predicting the impact of the increased levels of atmospheric CO 2 which are being generated anthropogenically depends upon quantification of sources, sinks and the processes inter-relating them.

Long-term Cyclic Variations of Prominences, Green and Red Coronae over Solar Cycles

2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský
Keyword(s):  
Emission Lines ◽  
High Latitudes ◽  
Green Line ◽  
Solar Cycles ◽  
The South ◽  
Coronal Emission ◽  
Local Maxima ◽  
The North ◽  
Cyclic Variations

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.

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