Freshwater shelled invertebrate indicators of paleoclimate in northwestern Canada during late glacial times

1977 ◽  
Vol 14 (9) ◽  
pp. 2029-2046 ◽  
Author(s):  
L. D. Delorme ◽  
S. C. Zoltai ◽  
L. L. Kalas
Keyword(s):  
Northwest Territories ◽  
Potential Evapotranspiration ◽  
Growing Season ◽  
Late Glacial ◽  
Annual Precipitation ◽  
Time Interval ◽  
Mean Annual Temperature ◽  
The Mean

Paleoclimatic interpretations based on shelled invertebrates from four sites in the northwest corner of the Northwest Territories, Canada, during the time interval 14 410–6820 years BP, indicate that the mean annual temperature was about 8.2–11.6 °C higher than at present, and that the annual precipitation was about 55–234 mm greater than at the present time. Based on potential evapotranspiration, it can be computed that the length of the growing season was about 156 days long as compared to between 90 and 135 growing days at the present time for the same area.

scholarly journals Inferencias paleoclimáticas para el Mioceno tardío en la cuenca de Angastaco basadas en el análisis fisionómico foliar: Formación Palo Pintado, Salta, Argentina

2020 ◽  
Vol 47 (2) ◽  
pp. 418
Author(s):  
Juan M. Robledo ◽  
Maricel Y. Horn ◽  
Claudia I. Galli ◽  
Luisa M. Anzótegui
Keyword(s):  
Late Miocene ◽  
Environmental Conditions ◽  
Sedimentary Rocks ◽  
Annual Precipitation ◽  
Mean Annual Precipitation ◽  
Mean Annual Temperature ◽  
Humid Environment ◽  
The Mean ◽  
La Rioja ◽  
Basin Region

The continental sedimentary rocks that constitute the Palo Pintado Formation of the late Miocene from Salta province, presents a great paleoclimatic interest due to the environmental conditions prevailing during this geochronologic interval. The geological and paleobotanical data suggest that during the sedimentary rocks accumulation of the Palo Pintado Formation (Angastaco Basin), wetter conditions would have existed comparing with other nearby and contemporary Formations, for example the Playa del Zorro Aloformation (late Miocene of Catamarca) and the Chiquimil (late Miocene of Tucumán), Salicas and the Toro Negro Formations (both from the late Miocene of La Rioja). In this study, the margin and the foliar area of the leaves contained on rocks from the Palo Pintado Formation are analyzed, in order to obtain the mean annual temperature (MAT) and the mean annual precipitation (MAP). The resulting values were: 23.98 °C and 330.8 mm. These results are coincident by the interpretation of different authors, who consider that the Palo Pintado Formation would have been deposited under a relatively humid environment, possibly as a consequence of the rains that affected locally the Angastaco basin región.

CLIMATIC TRENDS IN THE BEAVERLODGE AREA

1962 ◽  
Vol 42 (4) ◽  
pp. 698-706 ◽  
Author(s):  
A. C. Carder
Keyword(s):  
Warming Trend ◽  
Annual Precipitation ◽  
Mean Annual Temperature ◽  
Climatic Trends ◽  
Different Types ◽  
The Mean ◽  
To Come ◽  
Frost Free Period

Analysis of the weather records at Beaverlodge from 1916 to 1960 revealed that, although the mean annual temperature increased over this time only [Formula: see text], the warming trend in the spring and fall was for some reason three times greater. This latter condition is very likely responsible for the marked lengthening of frost-free period over the 45 years. Annual precipitation increased almost 2 inches with wetter springs, summers and autumns, but a decrease in winter snowfall. The tendency for warm, cool, wet or dry years to come in groups was marked, but there was no association between the occurrence of these different types of years. The data were insufficient to determine if any recurrence was cyclic.

scholarly journals Patterns and controls of soil respiration and its temperature sensitivity in grassland ecosystems across China

2018 ◽  
Author(s):  
Jiguang Feng ◽  
Jingsheng Wang ◽  
Yanjun Song ◽  
Biao Zhu
Keyword(s):  
Climate Change ◽  
Soil Respiration ◽  
Soil Temperature ◽  
Spatial Variation ◽  
Temperature Sensitivity ◽  
Annual Precipitation ◽  
Mean Annual Precipitation ◽  
Mean Annual Temperature ◽  
The Mean ◽  
Grassland Types

Abstract. Soil respiration (Rs), a key process in the terrestrial carbon cycle, is very sensitive to climate change. In this study, we synthesized 54 measurements of annual Rs and 171 estimates of Q10 value (the temperature sensitivity of soil respiration) in grasslands across China. We quantitatively analyzed their spatial patterns and controlling factors in five grassland types, including temperate typical steppe, temperate meadow steppe, temperate desert steppe, alpine grassland, and warm-tropical grassland. Results showed that the mean (± SE) annual Rs was 582.0 ± 57.9 g C m−2 yr−1 across Chinese grasslands. Annual Rs significantly differed among grassland types, and positively correlated with mean annual temperature, mean annual precipitation, soil organic carbon content and aboveground biomass, but negatively correlated with latitude and soil pH (P < 0.05). Among these factors, mean annual precipitation was the primary factor controlling the spatial variation of annual Rs in Chinese grasslands. The mean contributions of growing season Rs and heterotrophic respiration to annual Rs were 78.7 % and 72.8 %, respectively. Moreover, the mean (± SE) of Q10 across Chinese grasslands was 2.60 ± 0.08, ranging from 1.03 to 8.13, and varied largely within and among grassland types, and among soil temperature measurement depths. Generally, the seasonal variation of soil respiration in Chinese grasslands cannot be well explained by soil temperature using the van't Hoff equation. Longitude and altitude were the dominant driving factors and accounted for 26.0 % of the variation in Q10 derived by soil temperature at the depth of 5 cm. Overall, our findings advance our understanding of the spatial variation and environmental control of soil respiration and Q10 across Chinese grasslands, and also improve our ability to predict soil carbon efflux under climate change on the regional scale.

scholarly journals Pollen-Based Quantitative Reconstruction of Holocene Climate Changes in the Daihai Lake Area, Inner Mongolia, China

2010 ◽  
Vol 23 (11) ◽  
pp. 2856-2868 ◽  
Author(s):  
Qinghai Xu ◽  
Jule Xiao ◽  
Yuecong Li ◽  
Fang Tian ◽  
Takeshi Nakagawa
Keyword(s):  
Climate Changes ◽  
Early Holocene ◽  
Weighted Averaging ◽  
Annual Precipitation ◽  
Mean Annual Temperature ◽  
Lake Area ◽  
Holocene Climate ◽  
Daihai Lake ◽  
The Mean ◽  
The Impact

Abstract Vegetation around the Daihai Lake, northern China, is very sensitive to climate changes. In this paper, pollen-based quantitative climate reconstructions using three methods [weighted averaging partial least squares method (WAPLS), modern analog technique (MAT), and pollen response surface method (PRS)] were conducted to obtain robust reconstructions of Holocene climate changes in the Daihai Lake area. The result obtained by the three methods all consistently show the annual precipitation to have been 50–100 mm lower in the early Holocene, 100–200 mm higher in the Mid-Holocene, and 50–100 mm lower again in the late Holocene than at present. The WAPLS and the MAT methods also show quasi-synchronous oscillations of the mean annual temperature (Ta); 1°–2°C lower in the Early Holocene and 1°–3°C higher in the Mid-Holocene than today. The time period from 6200 to 5100 cal yr BP was the wettest and the warmest interval, with an annual precipitation (Pa) greater than 550 mm and mean annual temperature Ta higher than 6.5°C. Several cold and dry events can be identified to occur about 8200, 6000, and 4400 cal yr BP, with an annual precipitation less than 400 mm and a mean annual temperature colder than 4.5°C, respectively. The mean temperature of the warmest month (Tw) as reconstructed using both WAPLS and MAT methods was relatively stable during the Holocene, fluctuating about ±2°C relative to the present level, but the PRS method suggests more varied Tw values in both amplitude and frequency. After 1500 cal yr BP, no consistent pattern can be observed from these three different analyses, probably because of the impact of intensified human disturbances on the natural vegetation. The fluctuations of annual precipitation (Pa) correspond to that observed in Dongge Cave in southern China. The differences might be linked to Indian monsoon and East Asia monsoon climates or caused by the different degree of dating precision, different temporal resolution, and different sensitive response of climate proxies to the climate variations.

scholarly journals Towards Understanding Variability in Droughts in Response to Extreme Climate Conditions over the Different Agro-Ecological Zones of Pakistan

2021 ◽  
Vol 13 (12) ◽  
pp. 6910
Author(s):  
Adil Dilawar ◽  
Baozhang Chen ◽  
Arfan Arshad ◽  
Lifeng Guo ◽  
Muhammad Irfan Ehsan ◽  
...  
Keyword(s):  
Pearson Correlation ◽  
Principal Component ◽  
Mitigation Strategies ◽  
Precipitation Extremes ◽  
Climate Mitigation ◽  
Mean Annual Temperature ◽  
Climate Extreme ◽  
Ecological Zones ◽  
The Mean ◽  
Agro Ecological Zones

Here, we provided a comprehensive analysis of long-term drought and climate extreme patterns in the agro ecological zones (AEZs) of Pakistan during 1980–2019. Drought trends were investigated using the standardized precipitation evapotranspiration index (SPEI) at various timescales (SPEI-1, SPEI-3, SPEI-6, and SPEI-12). The results showed that droughts (seasonal and annual) were more persistent and severe in the southern, southwestern, southeastern, and central parts of the region. Drought exacerbated with slopes of −0.02, −0.07, −0.08, −0.01, and −0.02 per year. Drought prevailed in all AEZs in the spring season. The majority of AEZs in Pakistan’s southern, middle, and southwestern regions had experienced substantial warming. The mean annual temperature minimum (Tmin) increased faster than the mean annual temperature maximum (Tmax) in all zones. Precipitation decreased in the southern, northern, central, and southwestern parts of the region. Principal component analysis (PCA) revealed a robust increase in temperature extremes with a variance of 76% and a decrease in precipitation extremes with a variance of 91% in the region. Temperature and precipitation extremes indices had a strong Pearson correlation with drought events. Higher temperatures resulted in extreme drought (dry conditions), while higher precipitation levels resulted in wetting conditions (no drought) in different AEZs. In most AEZs, drought occurrences were more responsive to precipitation. The current findings are helpful for climate mitigation strategies and specific zonal efforts are needed to alleviate the environmental and societal impacts of drought.

scholarly journals TEVAR versus open repair of blunt traumatic descending aortic injury in polytraumatic patients involved in motor vehicle accidents

2021 ◽  
Vol 29 (1) ◽  
Author(s):  
Imthiaz Manoly ◽  
Mohamed El Tahan ◽  
Maymoona Al Shuaibi ◽  
Fatimah Adel ◽  
Mohammed Al Harbi ◽  
...  
Keyword(s):  
Blood Transfusion ◽  
Hospital Stay ◽  
Open Repair ◽  
Motor Vehicle ◽  
Aortic Injury ◽  
Motor Vehicle Accidents ◽  
Time Interval ◽  
Vehicle Accidents ◽  
Severity Scores ◽  
The Mean

Abstract Background Thoracic endovascular aortic repair (TEVAR) is the standard-of-care for treating traumatic aortic injury (TAI). Few retrospective studies compared TEVAR to open repair in blunt traumatic aortic injury (BTAI). Our objectives were to compare the early outcomes of TEVAR for blunt traumatic descending aortic injury to open repair (OR) in polytraumatic patients involved in motor vehicle accidents (MVA). Results Between February 2005 and April 2017, 71 patients with TAI due to MVA presented to our institution. All patients with descending aortic injuries were considered for open repair (n = 41) or TEVAR (n = 30) if there was no contraindication. The primary outcome was mortality, and secondary outcomes were stroke, paraplegia, intensive care unit (ICU), and hospital stay. The mean age was 28.4 ± 10.1 years in the OR group and 33.3 ± 16.6 years in TEVAR-group (P = 0.13). The injury severity scores were 41 ± 10 in the OR group and 33 ± 17 in the TEVAR group (P = 0.03). Patients in the OR group underwent emergency repair with a mean time of 0.56 ± 0.18 days from arrival. The TEVAR group had a longer time interval between arrival and procedure (2.1 ± 1.7 days, P = 0.001). The OR group had more blood transfusion (24 (58.5%) vs. 8 (27.5%), P = 0.002), renal impairment (6 (14.6%) vs. 1 (5.50%), P = 0.23), and wound infection (21 (51.2%) vs. 3 (10%), P < 0.001). Three TEVAR patients had a perioperative stroke compared to two patients in the OR group (P = 0.64). There was no difference in the mean ICU (6 ± 8.9 vs. 5.3 ± 2.9 days; P = 0.1) or hospital stay (20.1 ± 12.3 vs. 20.1 ± 18.3, P = 0.62) between the two groups. There were four deaths in the OR group and none in the TEVAR group (P = 0.13). Conclusion The results of TEVAR were comparable with the open repair for traumatic aortic injury with good early postoperative outcomes. TEVAR repair could be associated with lower mortality, blood transfusion, and infective complications. However, the complexity of the injury and technical challenges were higher in the open group.

scholarly journals Latitudinal distribution of microbial communities in anaerobic biological stabilization ponds: effect of the mean annual temperature

2016 ◽  
Vol 9 (6) ◽  
pp. 834-845 ◽  
Author(s):  
Mengdong Yuan ◽  
Jing Zhu ◽  
Cheng Wang ◽  
Mengxiong Wu ◽  
Faqian Sun ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Mean Annual Temperature ◽  
Latitudinal Distribution ◽  
Stabilization Ponds ◽  
The Mean

scholarly journals Sensitivity of groundwater recharge using climatic analogues and HYDRUS-1D

2012 ◽  
Vol 16 (8) ◽  
pp. 2485-2497 ◽  
Author(s):  
B. Leterme ◽  
D. Mallants ◽  
D. Jacques
Keyword(s):  
Water Balance ◽  
Groundwater Recharge ◽  
Potential Evapotranspiration ◽  
Future Climate ◽  
Annual Precipitation ◽  
Balance Model ◽  
Subtropical Climate ◽  
Northern Spain ◽  
Near Surface ◽  
Hydrus 1D

Abstract. The sensitivity of groundwater recharge to different climate conditions was simulated using the approach of climatic analogue stations, i.e. stations presently experiencing climatic conditions corresponding to a possible future climate state. The study was conducted in the context of a safety assessment of a future near-surface disposal facility for low and intermediate level short-lived radioactive waste in Belgium; this includes estimation of groundwater recharge for the next millennia. Groundwater recharge was simulated using the Richards based soil water balance model HYDRUS-1D and meteorological time series from analogue stations. This study used four analogue stations for a warmer subtropical climate with changes of average annual precipitation and potential evapotranspiration from −42% to +5% and from +8% to +82%, respectively, compared to the present-day climate. Resulting water balance calculations yielded a change in groundwater recharge ranging from a decrease of 72% to an increase of 3% for the four different analogue stations. The Gijon analogue station (Northern Spain), considered as the most representative for the near future climate state in the study area, shows an increase of 3% of groundwater recharge for a 5% increase of annual precipitation. Calculations for a colder (tundra) climate showed a change in groundwater recharge ranging from a decrease of 97% to an increase of 32% for four different analogue stations, with an annual precipitation change from −69% to −14% compared to the present-day climate.

scholarly journals Climate Change Patterns of Wild Blueberry Fields in Downeast, Maine over the Past 40 Years

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 594
Author(s):  
Rafa Tasnim ◽  
Francis Drummond ◽  
Yong-Jiang Zhang
Keyword(s):  
Climate Change ◽  
Vegetation Index ◽  
Potential Evapotranspiration ◽  
Growing Season ◽  
Spatial Average ◽  
Climate Variables ◽  
Threshold Values ◽  
The Past ◽  
Wild Blueberry ◽  
Crop Health

Maine, USA is the largest producer of wild blueberries (Vaccinium angustifolium Aiton), an important native North American fruit crop. Blueberry fields are mainly distributed in coastal glacial outwash plains which might not experience the same climate change patterns as the whole region. It is important to analyze the climate change patterns of wild blueberry fields and determine how they affect crop health so fields can be managed more efficiently under climate change. Trends in the maximum (Tmax), minimum (Tmin) and average (Tavg) temperatures, total precipitation (Ptotal), and potential evapotranspiration (PET) were evaluated for 26 wild blueberry fields in Downeast Maine during the growing season (May–September) over the past 40 years. The effects of these climate variables on the Maximum Enhanced Vegetation Index (EVImax) were evaluated using Remote Sensing products and Geographic Information System (GIS) tools. We found differences in the increase in growing season Tmax, Tmin, Tavg, and Ptotal between those fields and the overall spatial average for the region (state of Maine), as well as among the blueberry fields. The maximum, minimum, and average temperatures of the studied 26 wild blueberry fields in Downeast, Maine showed higher rates of increase than those of the entire region during the last 40 years. Fields closer to the coast showed higher rates of warming compared with the fields more distant from the coast. Consequently, PET has been also increasing in wild blueberry fields, with those at higher elevations showing lower increasing rates. Optimum climatic conditions (threshold values) during the growing season were explored based on observed significant quadratic relationships between the climate variables (Tmax and Ptotal), PET, and EVImax for those fields. An optimum Tmax and PET for EVImax at 22.4 °C and 145 mm/month suggest potential negative effects of further warming and increasing PET on crop health and productivity. These climate change patterns and associated physiological relationships, as well as threshold values, could provide important information for the planning and development of optimal management techniques for wild blueberry fields experiencing climate change.

ANALYSIS OF TRENDS OF TOTAL EVAPORATION FLUXES (FOR 2003-2017) ACCORDING TO THE DATA OF PRODUCT MOD16A2 FOR THE TERRITORY OF THE MARKSOVSKY DISTRICT OF THE SARATOV REGION

2021 ◽  
pp. 16-25
Author(s):  
O. S. ERMOLAEVA ◽  
◽  
A. M. ZEYLIGER
Keyword(s):  
Time Series ◽  
Irrigation System ◽  
Growing Season ◽  
Half Period ◽  
Anthropogenic Factors ◽  
Time Interval ◽  
Total Evaporation ◽  
Saratov Region ◽  
Growing Seasons ◽  
Dominant Part

This paper presents the results of calculations of areal trends of total evaporation ETa fl uxes for the growing periods of 2003-2017 in the territory of the Marksovsky district of the Saratov region. Raster layers formed for the territory with a 500 m resolution of the Eta8 (Eta 8-day averaging) for each year of the investigated time interval were obtained from tiles sets h20v03 of the product MOD16A2 for the period from May 25 to September 2 of the corresponding year. As a result, the 19830 time series of total evaporation fl uxes for the ETaw growing seasons of the 15-year study period were drawn up for the Marksovsky district. The obtained time series of geodata of the actual evapotranspiration for the growing season ETaw for each of the 15 studied years were used for the spatial analysis of ETaw trends. For the analysis, the method of nonparametric Mann-Kendal statistics was used. It revealed the presence of 2 half-periods with diametrically opposite trends in the dominant part of time series. The fi rst half-period found out negative values (downward) trends and falls on 2003-2010, the second half-period showed positive (upward) trends for 2010-2017. The presented results of the spatial distribution of both trends indicate the presence of an infl uence on ETaw both distance from the bank of R. Volga and anthropogenic factors. Hypotheses for additional analysis are proposed. For the visual deciphering of the places of abnormal values of trends velocities of the both half-periods there were used space photos of high resolution. As a result it was marked that the location of these anomalies corresponded to the location of pivot sprinklers in the territory of the Privolzhskoj irrigation system.

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