scholarly journals Changing Climatic Averages and Variance: Implications for Mesophication at the Eastern Edge of North America’s Eastern Deciduous Forest

Forests ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 605 ◽  
Author(s):  
Evan Kutta ◽  
Jason Hubbart
Keyword(s):  
Deciduous Forest ◽  
Fire Suppression ◽  
Maximum Temperature ◽  
Eastern Deciduous Forest ◽  
Temperature Variance ◽  
Forest Ecosystem Services ◽  
Maximum Temperatures ◽  
Eastern Edge ◽  
Climate Variance

Observed conversion of xerophytic warm genera species to mesophytic cool genera species in North America’s Eastern Deciduous Forest (EDF) suggests species composition is in disequilibrium with recent climatic warming. However, increasing annual average temperatures is an oversimplification of long-term climatic change and the importance of climate variance is often neglected. Seven-year moving averages and standard deviations of annually averaged maximum temperatures, minimum temperatures, daily precipitation, and vapor pressure deficits (VPD) in West Virginia, USA were quantified over a 111-year period of record (1906–2016). Maximum temperatures decreased significantly (−5.3%; p < 0.001), minimum temperatures increased significantly (7.7%; p < 0.001), and precipitation increased (2.2%; p = 0.107). Additionally, maximum temperature variance decreased (−17.4%; p = 0.109), minimum temperature variance decreased significantly (−22.6%; p = 0.042), and precipitation variance increased significantly (26.6%; p = 0.004). Results indicate a reduced diurnal temperature range and significant reductions in estimated VPD (10.3%; p < 0.001) that imply increased relative humidity, cloud cover, and soil moisture that may support increasingly abundant mesophytic cool genera species. Feedback mechanisms associated with extensive changes in land use, fire suppression, and browser population may have exacerbated climatic changes. Long-term assessments of changing climatic averages and variance are needed to ensure sustainability of forest ecosystem services, health, and productivity in a swiftly changing climate across the broader EDF region and similar temperate forest ecosystems globally.

scholarly journals MJO teleconnections to crop growing seasons

2020 ◽  
Vol 54 (3-4) ◽  
pp. 2203-2219 ◽  
Author(s):  
Weston Anderson ◽  
Ángel G. Muñoz ◽  
Lisa Goddard ◽  
Walter Baethgen ◽  
Xandre Chourio
Keyword(s):  
Soil Moisture ◽  
Daily Precipitation ◽  
Maximum Temperature ◽  
Growing Seasons ◽  
Air Temperatures ◽  
Summer Hemisphere ◽  
Leaf Level ◽  
Maximum Temperatures ◽  
The Tropics

AbstractWhile many Madden–Julian Oscillation (MJO) teleconnections are well documented, the significance of these teleconnections to agriculture is not well understood. Here we analyze how the MJO affects the climate during crop flowering seasons, when crops are particularly vulnerable to abiotic stress. Because the MJO is located in the tropics of the summer hemisphere and maize is a tropical, summer-grown crop, the MJO teleconnections to maize flowering seasons are stronger and more coherent than those to wheat, which tends to be grown in midlatitudes and flowers during the spring. The MJO significantly affects not only daily average precipitation and soil moisture, but also the probability of extreme precipitation, soil moisture and maximum temperatures during crop flowering seasons. The average influence on the probability of extreme daily precipitation, soil moisture, and maximum temperature events is roughly equal. On average the MJO modifies the probability of a 5th or 95th, 10th or 90th, and 25th or 75th percentile event by $$\sim $$∼ 2.5%, $$\sim $$∼ 4% and $$\sim $$∼ 7%, respectively. This means that an exceptionally dry (10th percentile) soil moisture value, for example, would become $$\sim $$∼ 40% more common (happening 14% of the time) during certain MJO phases. That the MJO can simultaneously dry soils and raise maximum air temperatures may be particularly damaging to crops because without available soil water during times of heat stress, plants are unable to transpire to cool leaf-level temperatures as a means of avoiding long-term damage. As a result, even though teleconnections from the MJO last only a few days to a week, they likely affect crop growth.

A 2000-year temperature reconstruction in the Animaqin Mountains of the Tibet Plateau, China

The Holocene ◽  
2016 ◽  
Vol 26 (12) ◽  
pp. 1904-1913 ◽  
Author(s):  
Feng Chen ◽  
Yong Zhang ◽  
Xuemei Shao ◽  
MingQi Li ◽  
Zhi-Yong Yin
Keyword(s):  
Ring Width ◽  
Temperature Reconstruction ◽  
Warming Trend ◽  
Tibet Plateau ◽  
Maximum Temperature ◽  
Eastern Tibetan Plateau ◽  
Recent Period ◽  
Variation Patterns ◽  
Maximum Temperatures

A 2665-year ring-width chronology was developed based on Qilian juniper from the upper treeline of the Animaqin Mountains on the eastern Tibetan Plateau. Correlation analysis results showed that the chronology was significantly negatively correlated with April–June maximum temperature at nearby meteorological stations, indicating that maximum temperature is the factor that limits tree growth in this area. Accordingly, we reconstructed the average April–June maximum temperature variations since 261 BC. Our regression model explained 37.9% of the total variance for the whole calibration period of 1960–2012. Our reconstruction revealed that the maximum temperature started to increase from approximately 1750 without a rapid warming trend, and the warmest period was from AD 890 to 947, as opposed to the recent period, whereas the period from AD 351–483 was the coldest. Significant periods in the wavelet power spectrum were approximately 2–8 years, 20–30 years, 30–60 years, and 60–130 years, as well as some long-term periods (more than 200 years). Comparisons with other temperature series from neighboring regions and the Northern Hemisphere as a whole support the validity of our reconstruction and suggest that it provides a representation of the temperature change for the Animaqin area, although asymmetric variation patterns in minimum and maximum temperatures were found.

scholarly journals Forty-Year Changes in the Avifauna of Grand Teton National Park, Wyoming, with Emphasis on Neotropical Migrants

1993 ◽  
Vol 17 ◽  
pp. 75-76
Author(s):  
Stephanie Jones ◽  
Fritz Knopf
Keyword(s):  
Latin American ◽  
National Park ◽  
Deciduous Forest ◽  
Human Impacts ◽  
Neotropical Migrants ◽  
Eastern Deciduous Forest ◽  
Data Set ◽  
Grand Teton National Park ◽  
Neotropical Migrant

Ornithologists and wildlife biologists have always been interested in documenting long-term changes in bird populations (e.g., Temple and Temple 1976, Kendeigh 1982). Long-term comparisons can assist in identifying patterns of change. These patterns, in turn, provide assistance in defining human impacts that may lead to some species or groups declining towards extirpation. One study specifically (Wilcove 1988) has had a major impact upon current resource issues within the Fish and Wildlife Service. That study used 40-year comparisons to confirm that fragmentation of the eastern deciduous forest had led to declines of neotropical migrants. The Wilcove (1988) study along with an essay (Hutto 1988) and an ecological study in New Hampshire (Holmes and Sherry 1988) were fundamental in identifying that declines in this group of birds cannot be blamed solely upon changes on Latin American wintering grounds. Missing from the neotropical migrant story, however, is an image of how neotropical migrants from western North America have changed in recent decades. An historical data set for comparison is available for seven vegetative associations in the vicinity of Jackson, Wyoming (Salt 1957). This project was begun in 1993 to replicate Salt's 1957 study in Grand Teton National Park. The work in 1993 was a pre-study to evaluate the potential for replicating Salt's study in the mid 1990's, 40 years after the original work.

Storm damage and long-term mortality in a semi-natural, temperate deciduous forest

2004 ◽  
Vol 188 (1-3) ◽  
pp. 197-210 ◽  
Author(s):  
Annett Wolf ◽  
Peter Friis Møller ◽  
Richard H.W. Bradshaw ◽  
Jaris Bigler
Keyword(s):  
Deciduous Forest ◽  
Storm Damage ◽  
Temperate Deciduous Forest ◽  
Temperate Deciduous ◽  
Long Term Mortality

THE TEMPERATURES OF SURFACE FIRES IN JACK PINE BARREN: I. THE VARIATION IN TEMPERATURE WITH TIME

1966 ◽  
Vol 44 (10) ◽  
pp. 1285-1292 ◽  
Author(s):  
David W. Smith ◽  
John H. Sparling
Keyword(s):  
Jack Pine ◽  
Maximum Temperature ◽  
Surface Fires ◽  
Mean Temperature ◽  
The Mean ◽  
Maximum Temperatures

The temperatures of 18 fires in an open jack pine barren near Timmins, Ontario, have been recorded. The maximum temperature recorded was 545 °C, although in other determinations fire temperatures in excess of 1000 °C were reached. The mean temperature of all fires was 340.6 ± 133.2 °C. Three fires at 230, 345, and 545 °C were considered in detail.The maximum temperature of a fire was normally recorded at heights of 5 cm or 10 cm above the surface. Maximum temperatures of hotter fires usually occurred at greater heights than cooler ones. Duration and the temperature ("intensity") of the fire are important aspects of fire studies.

scholarly journals A Typical Meteorological Year Generation Based on NASA Satellite Imagery (GEOS-I) for Sokoto, Nigeria

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Olayinka S. Ohunakin ◽  
Muyiwa S. Adaramola ◽  
Olanrewaju M. Oyewola ◽  
Richard L. Fagbenle ◽  
Fidelis I. Abam
Keyword(s):  
Energy Systems ◽  
Building Energy ◽  
Global Solar Radiation ◽  
Dew Point ◽  
Weather Data ◽  
Maximum Temperature ◽  
Building Energy Simulation ◽  
Dew Point Temperature ◽  
Northwest Region

Computer simulation of buildings and solar energy systems are being used increasingly in energy assessments and design. This paper evaluates the typical meteorological year (TMY) for Sokoto, northwest region, Nigeria, using 23-year hourly weather data including global solar radiation, dew point temperature, mean temperature, maximum temperature, minimum temperature, relative humidity, and wind speed. Filkenstein-Schafer statistical method was utilized for the creation of a TMY for the site. The persistence of mean dry bulb temperature and daily global horizontal radiation on the five candidate months were evaluated. TMY predictions were compared with the 23-year long-term average values and are found to have close agreement and can be used in building energy simulation for comparative energy efficiency study.

THE DISTRIBUTION OF DERMACENTOR TICKS IN CANADA IN RELATION TO BIOCLIMATIC ZONES

1967 ◽  
Vol 45 (4) ◽  
pp. 517-537 ◽  
Author(s):  
P. R. Wilkinson
Keyword(s):  
British Columbia ◽  
Deciduous Forest ◽  
Strong Association ◽  
Eastern Deciduous Forest ◽  
Egg Development ◽  
The North ◽  
Winter Activity ◽  
Bioclimatic Zone ◽  
Soil Temperatures ◽  
Time Of Year

Dermacentor andersoni has been collected north of Jasper, Alberta, close to 54° N. and near 53° N. in British Columbia. Spread to the north and northwest is probably limited by low summer soil temperatures, which would act principally by slowing egg development, thus disrupting the seasonal cycle of the tick. To the southwest, mild winters may fail to release diapause at the correct time of year. Aspect and slope are important factors. Altitude spread of records is from 1000–7000 ft. The most generally applicable description of its distribution is the ecotone between western grassland and moister regions, including clearings and rocky outcrops m the montane and Columbia forests, and shrubby areas of the prairies. In British Columbia, a series of randomly selected transects indicated a strong association between the tick's presence and several species of shrubs growing without tree shade.Each bioclimatic zone tends to have a characteristic group of rodents as main hosts of the immature stages. The prairie and montane regions differ in the indigenous hosts available to the adult tick.East of 105° D. andersoni is replaced by D. variabilis, which is adapted to the more humid summers of the eastern deciduous forest zones, and differs considerably from D. andersoni in its phenology. There are no reliable records of indigenous D. variabilis north of 52° latitude.D. albipictus occurs from the east to the west coast. Because of the winter activity of its larvae, allowing the whole summer for egg development, it is able to penetrate much farther north than the other two species. There are two records close to 60° latitude.

Hydrological variability and long-term floristic-structural modifications in different habitats of a tropical semi-deciduous forest

2021 ◽  
Author(s):  
Alisson Borges Miranda Santos ◽  
Vinicius Andrade Maia ◽  
Cléber Rodrigo de Souza ◽  
Natália de Aguiar-Campos ◽  
Aurélio de Jesus Rodrigues Pais ◽  
...  
Keyword(s):  
Deciduous Forest ◽  
Structural Modifications ◽  
Hydrological Variability
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