scholarly journals Aridy index over time in five ecosystems on semiarid

2019 ◽  
Vol 9 (3) ◽  
pp. 138
Author(s):  
Otacilio Antunes Santana ◽  
José Imaña Encinas ◽  
Bárbara Alves de Sousa ◽  
Sandra Razana Silva do Monte ◽  
Valéria Sandra de Oliveira Costa
Keyword(s):  
Climate Change ◽  
Land Use ◽  
Aridity Index ◽  
Arid Climate ◽  
Semiarid Area ◽  
Local Climate ◽  
Brazilian Semiarid ◽  
Environment Variables ◽  
Local Climate Change ◽  
Over Time

The local climate change was registered over time (1992-2018) on different land use ecosystems, in Brazilian Semiarid area. The aimed of this work was to analyze aridity index in five ecosystems (Wild Caatinga, Caatinga on management, Cactaceae field, Eucalyptus reforestation, and Fabaceae crop), and to compare this index with environment variables. Meteorological towers and measures with porometer and psychrometers were carried out to collect the data. The main result was that the studied areas are hotter and drier. The Fabaceae crop and Eucalyptus reforestation studied ecosystems already are on Arid classification according with registered aridity index. Wild Caatinga and Cactaceae field ecosystems are on Semiarid classification, and over time Caatinga on management ecosystem pass from Semiarid to Arid classification. The five ecosystems together are classified on Arid climate. The VPD and Ψsoil were the variables more directly proportional with Aridity index to analyzed ecosystems.

scholarly journals A Review of Ocean Dynamics in the North Atlantic: Achievements and Challenges

Climate ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 49
Author(s):  
Knut Lehre Seip
Keyword(s):  
Climate Change ◽  
Temperature Change ◽  
North Atlantic ◽  
Ocean Dynamics ◽  
Local Climate ◽  
The North ◽  
Local Climate Change ◽  
Global Temperature Change ◽  
The North Atlantic ◽  
Over Time

I address 12 issues related to the study of ocean dynamics and its impact on global temperature change, regional and local climate change, and on the North Atlantic ecosystem. I outline the present achievements and challenges that lie ahead. I start with observations and methods to extend the observations of ocean oscillations over time and end with challenges to find connections between ocean dynamics in the North Atlantic and dynamics in other parts of the globe.

scholarly journals Long-Term Trends in Spring Arrival Dates of Migrant Birds at Delta Marsh, Manitoba, in Relation to Climate Change

The Auk ◽  
2005 ◽  
Vol 122 (4) ◽  
pp. 1130-1148 ◽  
Author(s):  
Heather M. Murphy-Klassen ◽  
Todd J. Underwood ◽  
Spencer G. Sealy ◽  
Ashleigh A. Czyrnyj
Keyword(s):  
Climate Change ◽  
Data Set ◽  
Local Climate ◽  
Delta Marsh ◽  
Local Climate Change ◽  
Arrival Dates ◽  
Spring Arrival ◽  
Migrant Birds ◽  
Changements Climatiques ◽  
Over Time

Abstract We examined a 63-year data set of dates of first spring sightings for 96 species of migrant birds at Delta Marsh, Manitoba, and considered the influence of local climate change on those arrival dates. Mean monthly spring temperatures increased (0.6–3.8°C) for all four months considered; however, trends for February and March were stronger than those for April and May. Over the 63-year period, 27 species significantly altered their arrival dates. Most of those species arrived significantly earlier; whereas only two species, Greater Yellowlegs (Tringa melanoleuca) and Lesser Yellowlegs (T. flavipes), arrived significantly later over time. About half of the migrants showed significant relationships between arrival dates and mean temperature for their month of arrival. Fifteen species showed significantly earlier arrivals over time and a significant relationship between arrival date and temperature. We also characterized migrants by taxon, breeding status, and wintering location to determine whether there were any trends for altered arrivals within certain groups. Waterfowl, species that breed at Delta Marsh, and short-distance migrants showed slightly higher incidences of advancing arrival dates compared with other groups. Our results provide evidence that climate warming has influenced spring migration arrival dates of several species in Manitoba. Tendances à Long-terme des Dates d'Arrivée Printanières des Oiseaux Migrateurs dans le Delta Marsh, Manitoba, en Relation avec les Changements Climatiques

scholarly journals Heatwaves and Summer Urban Heat Islands: A Daily Cycle Approach to Unveil the Urban Thermal Signal Changes in Lisbon, Portugal

Atmosphere ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 292 ◽  
Author(s):  
Ana Oliveira ◽  
António Lopes ◽  
Ezequiel Correia ◽  
Samuel Niza ◽  
Amílcar Soares
Keyword(s):  
Climate Change ◽  
Air Temperature ◽  
Wind Direction ◽  
Urban Heat Islands ◽  
Daily Cycle ◽  
Local Climate ◽  
Thermal Signal ◽  
Air Temperatures ◽  
Local Climate Change ◽  
Urban Heat

Lisbon is a European Mediterranean city, greatly exposed to heatwaves (HW), according to recent trends and climate change prospects. Considering the Atlantic influence, air temperature observations from Lisbon’s mesoscale network are used to investigate the interactions between background weather and the urban thermal signal (UTS) in summer. Days are classified according to the prevailing regional wind direction, and hourly UTS is compared between HW and non-HW conditions. Northern-wind days predominate, revealing greater maximum air temperatures (up to 40 °C) and greater thermal amplitudes (approximately 10 °C), and account for 37 out of 49 HW days; southern-wind days have milder temperatures, and no HWs occur. Results show that the wind direction groups are significantly different. While southern-wind days have minor UTS variations, northern-wind days have a consistent UTS daily cycle: a diurnal urban cooling island (UCI) (often lower than –1.0 °C), a late afternoon peak urban heat island (UHI) (occasionally surpassing 4.0 °C), and a stable nocturnal UHI (1.5 °C median intensity). UHI/UCI intensities are not significantly different between HW and non-HW conditions, although the synoptic influence is noted. Results indicate that, in Lisbon, the UHI intensity does not increase during HW events, although it is significantly affected by wind. As such, local climate change adaptation strategies must be based on scenarios that account for the synergies between potential changes in regional air temperature and wind.

scholarly journals Local climate change signals and changes in climate extremes in a typical Sahel catchment: the case of Dano catchment, Burkina Faso

2021 ◽  
pp. 100285
Author(s):  
Gloria C. Okafor ◽  
Isaac Larbi ◽  
Emmanuel C. Chukwuma ◽  
Clement Nyamekye ◽  
Andrew Manoba Limantol ◽  
...  
Keyword(s):  
Climate Change ◽  
Burkina Faso ◽  
Climate Extremes ◽  
Local Climate ◽  
Local Climate Change
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