Predicting ecological changes on benthic estuarine assemblages through decadal climate trends along Brazilian Marine Ecoregions

2015 ◽  
Vol 166 ◽  
pp. 74-82 ◽  
Author(s):  
Angelo F. Bernardino ◽  
Sérgio A. Netto ◽  
Paulo R. Pagliosa ◽  
Francisco Barros ◽  
Ronaldo A. Christofoletti ◽  
...  
Keyword(s):  
Climate Trends ◽  
Ecological Changes ◽  
Decadal Climate

Decadal Climate Variation and Coho Salmon Catch

2003 ◽  
Author(s):  
David Greenland
Keyword(s):  
Pacific Northwest ◽  
Coho Salmon ◽  
Juvenile Fish ◽  
Early Summer ◽  
Air Temperatures ◽  
Ecological Changes ◽  
The Pacific ◽  
Freshwater Stream ◽  
Long Term Ecological Research ◽  
Decadal Climate

When temporally smoothed data are used for the period 1925 to 1985 there is a close inverse statistical relationship acting at an interdecadal timescale between the Pacific Northwest (PNW) air temperatures and Coho salmon catch off the coast of Washington and Oregon. This relationship is now well known, although not fully explained, but at the time of its discovery in 1994 it was part of advances being made by several research groups on interdecadal-scale climate/ecological changes in the PNW (Greenland 1995). The discovery and later, related findings may be usefully examined within the context of the framework questions of this book (see chapter 1) because it provides a very interesting example of climate variability and ecosystem response found, in part, by Long-Term Ecological Research (LTER) investigators. The logical progression for this chapter is first to review a little of the relationship between Coho salmon and climate and then to explain how a study at one LTER site led to a finding with regional implications. An update of the findings at interdecadal-scale climate/ecological changes in the PNW is then appropriate, followed by a discussion of the topic with the framework questions of this book. The PNW is defined, for the purposes of this chapter, as the area of Washington and Oregon west of the crest of the Cascade Range. The term decadal is used loosely in this chapter to refer to changes that focus on time periods of about 10 to 30 years in length. Salmon live part of their lives in terrestrial, freshwater environments and part in marine, saltwater environments. The salmon life history starts with fertilized eggs remaining in gravel in freshwater stream beds and hatching after 1–3 months. One to five months later, fry emerge in the spring or summer. Juvenile fish are in freshwater from a few days to 4 years, depending on species and locality. After the juveniles change to smolts, they can migrate to the ocean, usually in spring or early summer, often taking advantage of streamflows driven by snowmelt. The fish spend 1–4 years in the ocean and then return to their freshwater home stream to spawn and die. More specifically, the typical life cycle for Oregon Coho spans 3 years (18 months in freshwater and 18 months in the ocean).

scholarly journals Absence of internal multidecadal and interdecadal oscillations in climate model simulations

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Michael E. Mann ◽  
Byron A. Steinman ◽  
Sonya K. Miller
Keyword(s):  
Climate Model ◽  
Southern Oscillation ◽  
Low Frequency ◽  
Climate Trends ◽  
Internal Oscillation ◽  
Model Simulations ◽  
Control Climate ◽  
Climate Model Simulations ◽  
Decadal Climate ◽  
And Control

AbstractFor several decades the existence of interdecadal and multidecadal internal climate oscillations has been asserted by numerous studies based on analyses of historical observations, paleoclimatic data and climate model simulations. Here we use a combination of observational data and state-of-the-art forced and control climate model simulations to demonstrate the absence of consistent evidence for decadal or longer-term internal oscillatory signals that are distinguishable from climatic noise. Only variability in the interannual range associated with the El Niño/Southern Oscillation is found to be distinguishable from the noise background. A distinct (40–50 year timescale) spectral peak that appears in global surface temperature observations appears to reflect the response of the climate system to both anthropogenic and natural forcing rather than any intrinsic internal oscillation. These findings have implications both for the validity of previous studies attributing certain long-term climate trends to internal low-frequency climate cycles and for the prospect of decadal climate predictability.

scholarly journals Potential tropical Atlantic impacts on Pacific decadal climate trends

2016 ◽  
Vol 43 (13) ◽  
pp. 7143-7151 ◽  
Author(s):  
Y. Chikamoto ◽  
T. Mochizuki ◽  
A. Timmermann ◽  
M. Kimoto ◽  
M. Watanabe
Keyword(s):  
Tropical Atlantic ◽  
Climate Trends ◽  
Decadal Climate

Variability of the aerosol content in the tropical lower stratosphere from 2013 to 2019 as influenced by moderate volcanic eruptions

2021 ◽  
Author(s):  
Mariam Tidiga ◽  
Gwenaël Berthet ◽  
Fabrice Jegou ◽  
Adriana Bossolasco ◽  
Corinna Kloss ◽  
...  
Keyword(s):  
Lower Stratosphere ◽  
Climate Model ◽  
Volcanic Eruptions ◽  
Climate Trends ◽  
Asian Monsoon Region ◽  
Microphysical Properties ◽  
Radiative Impact ◽  
Decadal Climate ◽  
The Tropics

<p>The cumulative impacts of frequent moderate-magnitude eruptions on stratospheric aerosols were identified among the factors in recent decadal climate trends. Moderate volcanic eruptions are a recurrent source of sulfur dioxide (SO2) in the Upper Troposphere and Lower Stratosphere (UTLS) region and the resulting formation of sulfuric acid aerosol particles from the SO2 emitted provides sites for chemical reactions leading to enhancement of stratospheric optical depth (SAOD) and ozone depletion. Modelling properly the volcanic aerosol content and its evolution in this region is important for radiative impact issues. In this work, we explore the variability of the tropical UTLS aerosol content between 2013 and 2019, a period which was particularly impacted by moderate tropical and mid-latitude volcanic eruptions. For that purpose, space-borne observations from OMPS (version 2, datasets from GES DISC), and IASI, together with simulations by the Whole Atmosphere Community Climate Model (WACCM) coupled with the Community Aerosol and Radiation Model for Atmospheres (CARMA), are used. Different model sensitive experiments, particularly for the injection altitude and timing, have been conducted to evaluate how the model captures the aerosol plume in terms of content, optical and microphysical properties, transport and residence time. We find that the decay of the Calbuco and Kelud plumes observed by OMPS version 2 is well reproduced by the model. Comparisons with unique datasets in the tropical southern hemisphere from the NDACC Maïdo observatory (Reunion Island, France, 20.5°S, 55.5°E) show good agreement between the lidar SAOD observations and WACCM-CARMA SAOD simulations although we observe a difference in the altitude of the maximum aerosol concentration between the model and the in situ profile after Calbuco eruption in April 2015. A particular focus is also made on recent eruptions like Raikoke, Ambae and Ulawun. The plume of the Ambae volcano (15°S, 167°E) which erupted in July 2018 is shown to propagate to the northern hemisphere with some influence until summer 2019 in the Asian monsoon region. For the year 2019, we investigate how the Ulawun (5°S, 151°E; ~0.14 Tg of SO2) tropical eruption and the Raikoke mid-latitude eruption (48°N, 153°E; ~1.5Tg of SO2), have influenced the aerosol burden in the tropics.</p>

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.

scholarly journals Advances in Egyptian Mediterranean Coast Climate Change Monitoring

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1870
Author(s):  
Matteo Gentilucci ◽  
Abdelraouf A. Moustafa ◽  
Fagr Kh. Abdel-Gawad ◽  
Samira R. Mansour ◽  
Maria Rosaria Coppola ◽  
...  
Keyword(s):  
Climate Change ◽  
Fish Species ◽  
Mitochondrial Gene ◽  
Mediterranean Coast ◽  
Sea Surface ◽  
Homogeneity Test ◽  
Sea Surface Temperatures ◽  
Climate Trends ◽  
Surface Temperatures ◽  
Lessepsian Species

This paper characterizes non-indigenous fish species (NIS) and analyses both atmospheric and sea surface temperatures for the Mediterranean coast of Egypt from 1991 to 2020, in relation to previous reports in the same areas. Taxonomical characterization depicts 47 NIS from the Suez Canal (Lessepsian/alien) and 5 from the Atlantic provenance. GenBank accession number of the NIS mitochondrial gene, cytochrome oxidase 1, reproductive and commercial biodata, and a schematic Inkscape drawing for the most harmful Lessepsian species were reported. For sea surface temperatures (SST), an increase of 1.2 °C to 1.6 °C was observed using GIS software. The lack of linear correlation between annual air temperature and annual SST at the same detection points (Pearson r) could suggest a difference in submarine currents, whereas the Pettitt homogeneity test highlights a temperature breakpoint in 2005–2006 that may have favoured the settlement of non-indigenous fauna in the coastal sites of Damiette, El Arish, El Hammam, Alexandria, El Alamain, and Mersa Matruh, while there seems to be a breakpoint present in 2001 for El Sallum. This assessment of climate trends is in good agreement with the previous sightings of non-native fish species. New insights into the assessment of Egyptian coastal climate change are discussed.

scholarly journals Detecting Climate Driven Changes in Chlorophyll-a in Deep Subalpine Lakes Using Long Term Satellite Data

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 866
Author(s):  
Gary Free ◽  
Mariano Bresciani ◽  
Monica Pinardi ◽  
Nicola Ghirardi ◽  
Giulia Luciani ◽  
...  
Keyword(s):  
Climate Change ◽  
Chlorophyll A ◽  
Nutrient Dynamics ◽  
Cascading Effects ◽  
The North ◽  
Subalpine Lakes ◽  
Winter Temperatures ◽  
Decadal Climate ◽  
The North Atlantic Oscillation ◽  
Traditional Pattern

Climate change has increased the temperature and altered the mixing regime of high-value lakes in the subalpine region of Northern Italy. Remote sensing of chlorophyll-a can help provide a time series to allow an assessment of the ecological implications of this. Non-parametric multiplicative regression (NPMR) was used to visualize and understand the changes that have occurred between 2003–2018 in Lakes Garda, Como, Iseo, and Maggiore. In all four deep subalpine lakes, there has been a disruption from a traditional pattern of a significant spring chlorophyll-a peak followed by a clear water phase and summer/autumn peaks. This was replaced after 2010–2012, with lower spring peaks and a tendency for annual maxima to occur in summer. There was a tendency for this switch to be interspersed by a two-year period of low chlorophyll-a. Variables that were significant in NPMR included time, air temperature, total phosphorus, winter temperature, and winter values for the North Atlantic Oscillation. The change from spring to summer chlorophyll-a maxima, relatively sudden in an ecological context, could be interpreted as a regime shift. The cause was probably cascading effects from increased winter temperatures, reduced winter mixing, and altered nutrient dynamics. Future trends will depend on climate change and inter-decadal climate drivers.

scholarly journals Past climate variations recorded in needle-like aragonites correlate with organic carbon burial efficiency as revealed by lake sediments in Croatia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ivan Razum ◽  
Petra Bajo ◽  
Dea Brunović ◽  
Nikolina Ilijanić ◽  
Ozren Hasan ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Stable Carbon Isotope ◽  
Climate Variations ◽  
Before Present ◽  
Stable Carbon ◽  
Climate Trends ◽  
Geochemical Proxies ◽  
Carbon Burial ◽  
Organic Carbon Burial ◽  
Burial Efficiency

AbstractThe drivers of organic carbon (OC) burial efficiency are still poorly understood despite their key role in reliable projections of future climate trends. Here, we provide insights on this issue by presenting a paleoclimate time series of sediments, including the OC contents, from Lake Veliko jezero, Croatia. The Sr/Ca ratios of the bulk sediment are mainly derived from the strontium (Sr) and calcium (Ca) concentrations of needle-like aragonite in Core M1-A and used as paleotemperature and paleohydrology indicators. Four major and six minor cold and dry events were detected in the interval from 8.3 to 2.6 calibrated kilo anno before present (cal ka BP). The combined assessment of Sr/Ca ratios, OC content, carbon/nitrogen (C/N) ratios, stable carbon isotope (δ13C) ratios, and modeled geochemical proxies for paleoredox conditions and aeolian input revealed that cold and dry climate states promoted anoxic conditions in the lake, thereby enhancing organic matter preservation and increasing the OC burial efficiency. Our study shows that the projected future increase in temperature might play an important role in the OC burial efficiency of meromictic lakes.

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