Modern Warming and the 35-Year Cool Period Within

2019 ◽  
pp. 33-37
Author(s):  
Rex J. Fleming
Keyword(s):  
Cool Period

scholarly journals The Effect of High Summer Temperatures on Reproduction in Holstein and Czech Fleckvieh

2020 ◽  
Vol 68 (1) ◽  
pp. 9-16
Author(s):  
Jiří Bezdíček ◽  
Andrea Nesvadbová ◽  
František Louda
Keyword(s):  
Milk Production ◽  
Summer Season ◽  
Cool Season ◽  
Length Of Service ◽  
Cool Period ◽  
Service Period ◽  
Summer Temperatures ◽  
The Difference

The aim of this study was to evaluate the effect of the hot summer season on the length of service period (number of days from calving to the next conception). For the analysis was created two databases of twins. Twins had the same sire and dam and the first and second lactations took place on the same farm. In the first database (105 pairs) one of the twins was calved (and had the following service period) during the summer months and the second of the twin was calved in the cooler months. To compare the difference in service period between twins in the hot and cool seasons, it was made also second group of twin pairs with reproduction only during the cool period of the year (cool vs. cool season; 58 pairs). The data were analysed using PROC GLM of Statistica®. In addition to season, the effect of breed (Holstein, Czech Fleckvieh), milk production at 1st lactation and calving year were also taken into consideration. The results showed a significantly longer service period in the summer (133.8 days) than in the cool months (114.7 days). In the case of twins with reproduction in the cool months of the year, the difference between length of service period was shorter and insignificant (113.6 vs. 119.4 days).

Measurement of rill erosion by snowmelt on potato fields under rotation in Prince Edward Island (Canada)

1998 ◽  
Vol 78 (3) ◽  
pp. 449-458 ◽  
Author(s):  
Linnell Edwards ◽  
G. Richter ◽  
B. Bernsdorf ◽  
R.-G. Schmidt ◽  
J. Burney
Keyword(s):  
Coming Out ◽  
Prince Edward Island ◽  
Soil Loss ◽  
Solanum Tuberosum L ◽  
Sediment Deposition ◽  
Cereal Grains ◽  
Rill Erosion ◽  
Cool Period ◽  
Volume Measurements ◽  
Potato Rotation

Cool-period soil erosion from farmland in Prince Edward Island occurs predominantly through rilling mainly due to snowmelt. This is mostly evident on fields coming out of potatoes (Solanum tuberosum L.), a crop that is traditionally cultivated as part of a 2-yr rotation with cereal grains, or a 3-yr rotation with cereal grains and a forage crop for hay. Accurate assessment of snowmelt erosion (associated processes and effects) has been historically constrained by data inadequacy, particularly for rilling; and although a number of models have now been developed for estimating cool-period erosion, they still stand to benefit from the generation of actual field data. In the present study, actual volume measurements were made of erosion forms, for about 80 site-years, after the spring snowmelt in fields at various stages of potato rotation. Cool-period erosion, predominantly rills, amounted to about 30 t ha−1 for 2-yr and 3-yr rotations, thus an annual seasonal average of 15 t ha−1 and 10 t ha−1, respectively. Potato fields left untilled over winter averaged about 20 t ha–1 which increased to 36 t ha−1 with fall ploughing. Sediment deposition in fields coming out of potatoes was 13.3 t ha−1 compared with the amount of 0.4 t ha−1 in fields coming out of forages and 1.6 t ha−1 in fields coming out of grain. Fields going into the winter in sod or stubble showed negligible erosion, averaging about 0.1 t ha−1 in spring. The results of this study demonstrate the dominant influence of cropping practice in the erosion process during the cool period, and the tendency for traditional computational procedures to underestimate soil loss. Key words: Cool-period erosion, rilling, rill volume, sediment deposition, soil-loss prediction, erosion mapping, crop rotation

scholarly journals Vegetation changes in the Hotyn Upland over the last 2000 years (based on pollen data)

2019 ◽  
Vol 28 (1) ◽  
pp. 51-58 ◽  
Author(s):  
N. Gerasimenko ◽  
T. Yurchenko ◽  
Ye. Rohozin
Keyword(s):  
Little Ice Age ◽  
Environmental Changes ◽  
Medieval Warm Period ◽  
Warm Period ◽  
Ice Age ◽  
Humid Climate ◽  
Cool Period ◽  
Surface Samples ◽  
Pollen Surface ◽  
Short Period

Pollen study of two soil sections, located in two different relief positions (the gully bottom at Sadgora 1 and the upper part of a slope at Ridkivtsi I) enables us to show vegetational and climatic changes in the Bukovyna area (the Chernivtsi region) during the last 2000 years (the end of the Early Subatlantic, the Middle and Late Subatlantic). The reconstructions of past vegetation are based on the analyses of pollen surface samples, taken from the soils of different ecotops in the sites’ vicinity. The reconstructed short-period phases of environmental change correspond well with those established in other areas. These are the end of the “Roman warm period” (before the 14C date of 1.74 ka BP), with the humid climate; the relatively dry “Dark Ages cool period” (before the 14C date of 1.19 ka BP); the wet “Medieval warm period”; the cool “Little Ice Age” (with its wetter beginning and drier ending) and the modern warm phase (the last 150 years).Centennial environmental changes − the cooling within the Medieval Warming (XI cent.) and the warming within the “Little Ice Age” (XV cent.) – have been detected. Human impact on the vegetation can be demonstrated – forest clearance (with the presence of particles of microscopic charcoal and pollen of pyrophitic plants), the introduction of thermophilous walnut during warm periods, and the appearance of pasture lands in the place of former fern patches and woods during the “Little Ice Age”, and the last warm phase (with the presence of pollen of pastoral synanthropic plants). In the last 2000 years, broad-leaved woodland, dominated by hornbeam, grew extensively near Sadgora and Ridkivtsi only during the “Medieval Warm Period”.

scholarly journals First record of a cold-period myxomycete species Dianema depressum (Lister) Lister in Poland

2017 ◽  
Vol 52 (1) ◽  
Author(s):  
Piotr Chachuła ◽  
Marek Fiedor ◽  
Anna Ronikier
Keyword(s):  
First Record ◽  
Cold Period ◽  
Species Occurrence ◽  
Cool Period ◽  
The Carpathians ◽  
Typical Time ◽  
First Time

A myxomycete species, <em>Dianema depressum</em> is reported for the first time in Poland. It has been found in the Jaszowiec stream valley, localized in the Beskid Śląski Mts (the Carpathians) in November 2015. The cool period seems to be the typical time of the species’ occurrence.

scholarly journals Twin Pregnancies in Dairy Cattle: Observations in a Large Herd of Holstein-Friesian Dairy Cows

Animals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2165
Author(s):  
Fernando López-Gatius ◽  
Irina Garcia-Ispierto ◽  
Ronald H. F. Hunter
Keyword(s):  
Dairy Cattle ◽  
Multiple Pregnancy ◽  
Warm Season ◽  
Uterine Horn ◽  
Warm Period ◽  
Multiple Pregnancies ◽  
Cool Period ◽  
Holstein Friesian ◽  
Large Herd ◽  
Twin Pregnancies

Multiple pregnancies have devastating consequences on the herd economy of dairy cattle. This observational study examines incidence patterns based on data from the ultrasonographic examination of 1130 multiple pregnancies in cows in their third lactation or more carrying twins (98.8%), triplets (1.1%), or quadruplets (0.08%), and 3160 of their peers carrying singletons. Cows became pregnant following a spontaneous estrus with no previous hormone treatments. Irrespective of a significant decrease (p < 0.0001) in the conception rate (28–34 days post-insemination) during the warm period of the year, the multiple pregnancy rate was similar for both warm (26.5%) and cool (26.3%) periods. The incidence of unilateral multiple pregnancies (all embryos in the same uterine horn) was higher than that of bilateral pregnancies (at least one embryo in each uterine horn): 54.4% versus 45.6% (p < 0.0001). This difference rose to 17% during the warm season (p = 0.03). Pregnancy was monitored in unilateral multiple pregnancies until abortion or parturition (n = 615). In the warm period, the parturition rate was 43% compared to 61% recorded in the cool period (p < 0.0001). Thus, a warm climate is the main factor compromising the fate of multiple pregnancies. Some clinical suggestions are provided.

Deglaciation chronology and revegetation in northwestern Ontario

1985 ◽  
Vol 22 (6) ◽  
pp. 850-871 ◽  
Author(s):  
Svante Björck
Keyword(s):  
Black Spruce ◽  
Lake Superior ◽  
The South ◽  
Migration Routes ◽  
White Pine ◽  
Cool Period ◽  
Radiocarbon Dates ◽  
Northwestern Ontario ◽  
History Of ◽  
Ice Retreat

Along a 420 km transect in northwestern Ontario, Canada, sediments from four lakes were analyzed with respect to lithology, pollen, and macrofossils. Radiocarbon dates show that the region was deglaciated between ca. 11 500 and 8000 years BP, and periods of both rapid ice retreat and readvance influenced the history of Glacial Lake Agassiz. In the south the ice sheet was succeeded by a lengthy interval of park–tundra with stands of spruce, ash, and elm. The ash and elm seem to have disappeared during a suggested cool period (11 100–10 200 years BP). Farther north the park–tundra phase lasted not more than 50–100 years after ca. 10 200 years BP before boreal trees dominated. The climatic change around 10 200 years BP permitted the very rapid migration of spruce, larch, birch, and jack or red pine into northwestern Ontario from northern Minnesota. The migration routes for Pinus strobus (white pine), Alnus rugosa, and A. crispa were divided, however: one from the south (south of Lake Superior) and one from the east-southeast (north of Lake Superior). White pine reached its maximum distribution 6500–6000 years BP, when the limit was probably 150–200 km north of today's. The composition of the boreal forest during the altithermal was only slightly changed, but the influx of presumed prairie pollen reached a peak ca. 8000–7000 years BP. Since then Picea mariana (black spruce) gradually became the dominating tree species.

scholarly journals Experiments based on blue intensity for reconstructing North Pacific temperatures along the Gulf of Alaska

2017 ◽  
Vol 13 (8) ◽  
pp. 1007-1022 ◽  
Author(s):  
Rob Wilson ◽  
Rosanne D'Arrigo ◽  
Laia Andreu-Hayles ◽  
Rose Oelkers ◽  
Greg Wiles ◽  
...  
Keyword(s):  
Tree Ring ◽  
North Pacific ◽  
Ring Width ◽  
Gulf Of Alaska ◽  
Climate Response ◽  
Cool Period ◽  
Climate Signal ◽  
Latewood Density ◽  
Blue Intensity

Abstract. Ring-width (RW) records from the Gulf of Alaska (GOA) have yielded a valuable long-term perspective for North Pacific changes on decadal to longer timescales in prior studies but contain a broad winter to late summer seasonal climate response. Similar to the highly climate-sensitive maximum latewood density (MXD) proxy, the blue intensity (BI) parameter has recently been shown to correlate well with year-to-year warm-season temperatures for a number of sites at northern latitudes. Since BI records are much less labour intensive and expensive to generate than MXD, such data hold great potential value for future tree-ring studies in the GOA and other regions in mid- to high latitudes. Here we explore the potential for improving tree-ring-based reconstructions using combinations of RW- and BI-related parameters (latewood BI and delta BI) from an experimental subset of samples at eight mountain hemlock (Tsuga mertensiana) sites along the GOA. This is the first study for the hemlock genus using BI data. We find that using either inverted latewood BI (LWBinv) or delta BI (DB) can improve the amount of explained temperature variance by > 10 % compared to RW alone, although the optimal target season shrinks to June–September, which may have implications for studying ocean–atmosphere variability in the region. One challenge in building these BI records is that resin extraction did not remove colour differences between the heartwood and sapwood; thus, long term trend biases, expressed as relatively warm temperatures in the 18th century, were noted when using the LWBinv data. Using DB appeared to overcome these trend biases, resulting in a reconstruction expressing 18th–19th century temperatures ca. 0.5 °C cooler than the 20th–21st centuries. This cool period agrees well with previous dendroclimatic studies and the glacial advance record in the region. Continuing BI measurement in the GOA region must focus on sampling and measuring more trees per site (> 20) and compiling more sites to overcome site-specific factors affecting climate response and using subfossil material to extend the record. Although LWBinv captures the inter-annual climate signal more strongly than DB, DB appears to better capture long-term secular trends that agree with other proxy archives in the region. Great care is needed, however, when implementing different detrending options and more experimentation is necessary to assess the utility of DB for different conifer species around the Northern Hemisphere.

scholarly journals Spatial and morphological change on Eliot Glacier, Mount Hood, Oregon, USA

2007 ◽  
Vol 46 ◽  
pp. 222-226 ◽  
Author(s):  
Keith M. Jackson ◽  
Andrew G. Fountain
Keyword(s):  
Global Warming ◽  
Morphological Change ◽  
Spatial Variations ◽  
Primary Factor ◽  
Ice Thickness ◽  
Ablation Zone ◽  
Kinematic Wave ◽  
Cool Period ◽  
Mount Hood

AbstractEliot Glacier is a small (1.6 km2) glacier on Mount Hood, Oregon, USA, and its ablation zone is largely covered with rock debris. We examine the interrelated processes of ablation rates, ice thickness and surface velocities to understand the retreat rate of this glacier. Since measurements began in 1901, the glacier has retreated 680 m, lost 19% of its area and thinned by about 50 m at the lower glacier profile before the terminus retreated past that point. The upper profile, 800m up-glacier, has shown thinning and thickening due to a kinematic wave resulting from a cool period during the 1940s–70s, and is currently about the same thickness as in 1940. Overall, the glacier has retreated at a slower rate than other glaciers on Mount Hood. We hypothesize that the rock debris covering the ablation zone reduces Eliot Glacier’s sensitivity to global warming and slows its retreat rate compared to other glaciers on Mount Hood. Spatial variations in debris thickness are the primary factor in controlling spatial variations in melt. A continuity model of debris thickness shows the rate of debris thickening down-glacier is roughly constant and is a result of the compensating effects of strain thickening and debris melt-out from the ice.

Diatom Evidence on Wisconsin and Holocene Events in the Bering Sea

1983 ◽  
Vol 20 (2) ◽  
pp. 232-245 ◽  
Author(s):  
Constance Sancetta ◽  
Stephen W. Robinson
Keyword(s):  
Sea Ice ◽  
Bering Sea ◽  
North Pacific Ocean ◽  
Ice Cover ◽  
Phytoplankton Productivity ◽  
Cool Period ◽  
Marginal Seas ◽  
The North ◽  
Ocean Environment ◽  
The Bering Sea

Previous work on surface (modern) sediments has defined diatom species which appear to be good indicators of various oceanographic/ecologic conditions in the North Pacific Ocean and marginal seas. Three long cores from the eastern and northern sides of the Aleutian Basin show changes in species assemblage which can be interpreted in terms of changes in the ocean environment during the last glaciation (Wisconsin) and the Holocene. The early and late Wisconsin maxima were times of prolonged annual sea-ice cover and a short cool period of phytoplankton productivity during the ice-free season. The middle Wisconsin interstade, at least in the southern Bering Sea, had greater seasonal contrast than today, with some winter sea-ice cover, an intensified temperature minimum, and high spring productivity. Variations in clastic and reworked fossil material imply varying degrees of transport to the basin by Alaskan rivers. The results of Jousé from the central Bering Sea generally correspond with those presented here, although there are problems with direct comparison.

Monsoon variability and chemical weathering during the late Pleistocene in the Goriganga basin, higher central Himalaya, India

2011 ◽  
Vol 75 (3) ◽  
pp. 597-604 ◽  
Author(s):  
Steven P. Beukema ◽  
R.V. Krishnamurthy ◽  
N. Juyal ◽  
N. Basavaiah ◽  
A.K. Singhvi
Keyword(s):  
Late Pleistocene ◽  
Chemical Weathering ◽  
Isotope Analysis ◽  
Luminescence Dating ◽  
Lake Basin ◽  
Central Himalaya ◽  
Cool Period ◽  
Monsoon Variability ◽  
Potential Use ◽  
Moderate Climate

AbstractStable isotope analysis along with radiocarbon and luminescence dating of late Pleistocene lacustrine deposits at Burfu in the higher central Himalaya are used to interpret hydrologic changes in the lake basin. From 15.5 ka to ~ 14.5 ka the Burfu lake was largely fed by melting glaciers. A warming event at 14.5 ka suggests an enhanced monsoon and increased carbonate weathering. From ~ 13.5 ka to ~ 12.5 ka the isotopic data suggest large-amplitude climate variability. Following this, the isotope data suggest a short-lived, abrupt cooling event, comprising a ~ 300-yr intense cool period followed by a ~ 500-yr interval of moderate climate. A shift in isotope values at ~ 11.3 ka may signify a strengthening monsoon in this region. The inferred climatic excursions appear to be correlative, at least qualitatively, with global climatic events, and perhaps the Burfu lake sequence provides regional evidence of globally recorded excursions. This study also suggests a potential use of radiocarbon ages in specific environments as a paleoenvironmental proxy.

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