EVALUATION OF CLIMATIC AND PHYSICAL CONTROLS AND THE INFLUENCE OF ENSO EVENTS ON LONG-TERM WEATHERING AND CO2 CONSUMPTION ACROSS THE PANAMA CANAL WATERSHED

The population trend over the last decade for subantarctic fur seals (Arctocephalus tropicalis) on Amsterdam and St. Paul islands and on Possession Island (Crozet Archipelago) and Antarctic fur seals (A. gazella) on Possession Island are analysed. At Amsterdam Island, based on pup counts, the subantarctic fur seal population appears to have stabilized after a period of rapid growth. At Possession Island subantarctic fur seal and Antarctic fur seal, with respective annual growth rates of 19.2 and 17.4%, are reaching the maximum growth rate for the genus Arctocephalus. Annual pup censuses at Possession Island since 1978 indicate important variations from year to year with pup production for A. gazella significantly lower the year after an El Niño Southern Oscillation (ENSO) event, but with no such relationship for A. tropicalis. Several other long term demographic studies of seabirds and marine mammals at different breeding locations in the Southern Ocean indicate that the breeding success of several of these predators appears to be widely affected in years which appear to be related to the ENSO events. To clarify this, it is necessary to analyse in more detail the demographic data obtained for the different subantarctic and Antarctic locations where long term monitoring programmes are conducted.

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The Hadley Circulation Regime Change: Combined Effect of the Western Pacific Warming and Increased ENSO Amplitude

Journal of Climate ◽

10.1175/jcli-d-18-0306.1 ◽

2018 ◽

Vol 31 (23) ◽

pp. 9739-9751 ◽

Cited By ~ 2

Author(s):

Yi-Peng Guo ◽

Zhe-Min Tan

Keyword(s):

Regime Change ◽

Southern Oscillation ◽

Hadley Circulation ◽

Warming Trend ◽

Combined Effect ◽

Western Pacific ◽

South Pacific Convergence Zone ◽

Boreal Winter ◽

Enso Events

The variation in the interannual relationship between the boreal winter Hadley circulation (HC) and El Niño–Southern Oscillation (ENSO) during 1948–2014 is investigated. The interannual variability of the HC is dominated by two principal modes: the equatorial asymmetric mode (AM) and the equatorial symmetric mode (SM). The AM of the HC during ENSO events mainly results from a combined effect of the ENSO sea surface temperature (SST) anomalies and the climatological background SST over the South Pacific convergence zone. Comparatively, the SM shows a steady and statistically significant relationship with ENSO; however, the interannual relationship between the AM and ENSO is strengthened during the mid-1970s, which leads to a HC regime change—that is, the interannual pulse of the HC intensity and its response to ENSO are stronger after the mid-1970s than before. The long-term warming trend of the tropical western Pacific since the 1950s and the increased ENSO amplitude play vital roles in the HC regime change. Although the tropical eastern Pacific also experienced a long-term warming trend, it has little influence on the HC regime change due to the climatologically cold background SST over the cold tongue region.

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Inter-Calibration of nine UV sensing instruments over Antarctica and Greenland since 1980: impact on global UV cloud albedo trends

10.5194/egusphere-egu2020-10856 ◽

2020 ◽

Author(s):

Clark Weaver ◽

Gordon Labow ◽

Dong Wu ◽

Pawan K. Bhartia ◽

David Haffner

Keyword(s):

Zenith Angle ◽

Forest Fires ◽

Solar Zenith Angle ◽

Radiative Transfer Model ◽

Transfer Model ◽

Cloud Albedo ◽

Enso Events ◽

Modeling Analysis ◽

Long Term Trend

<p>A suite of NASA/NOAA UV (340nm) sensing satellite instruments, starting with Nimbus-7 SBUV in 1980, provides a global long-term record of cloud trends and cloud response from ENSO events. We present new method to inter-calibrate the radiances of all the SBUV instruments and the Suomi NPP OMPS mapper over both the East Antarctic Plateau and Greenland ice sheets during summer. First, the strong solar zenith angle dependence from the intensities are removed using an empirical approach rather than a radiative transfer model. Then small multiplicative adjustments are made to these solar zenith angle normalized intensities in order to minimize differences when two or more instruments temporally overlap. While the calibrated intensities show a negligible long-term trend over Antarctica, and a statistically insignificant UV albedo trend of -0.05 % per decade over the interior of Greenland, there are small episodic reductions in&#160;intensities which are often seen by multiple instruments. Three of these darkening events are explained by boreal forest fires using trajectory modeling analysis. Other events are caused by surface melting or volcanoes. We estimate a 2-sigma uncertainty&#160;of 0.35% for the calibrated radiances. Finally, we connect the estimated radiance uncertainties, derived from our calibration approach, to the tropical and midlatitude UV cloud albedo trends.</p>

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Droughts pose long-term challenges for Panama Canal

Emerald Expert Briefings ◽

10.1108/oxan-es243596 ◽

2019 ◽

Keyword(s):

Panama Canal ◽

Content Type

Headline PANAMA: Droughts pose long-term challenges for Canal

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Large-scale climatic phenomena drive fluctuations in macroinvertebrate assemblages in lowland tropical streams, Costa Rica: The importance of ENSO events in determining long-term (15y) patterns

PLoS ONE ◽

10.1371/journal.pone.0191781 ◽

2018 ◽

Vol 13 (2) ◽

pp. e0191781 ◽

Cited By ~ 16

Author(s):

Pablo E. Gutiérrez-Fonseca ◽

Alonso Ramírez ◽

Catherine M. Pringle

Keyword(s):

Costa Rica ◽

Large Scale ◽

Tropical Streams ◽

Macroinvertebrate Assemblages ◽

Enso Events

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On the spatial and temporal variability of ENSO precipitation and drought teleconnection in mainland Southeast Asia

Climate of the Past Discussions ◽

10.5194/cpd-11-5307-2015 ◽

2015 ◽

Vol 11 (6) ◽

pp. 5307-5343 ◽

Cited By ~ 3

Author(s):

T. A. Räsänen ◽

V. Lindgren ◽

J. H. A. Guillaume ◽

B. M. Buckley ◽

M. Kummu

Keyword(s):

Southeast Asia ◽

Southern Oscillation ◽

Drought Severity ◽

Spatial And Temporal Variability ◽

Severe Drought ◽

Seasonal Evolution ◽

Enso Events ◽

Precipitation Anomalies ◽

Mainland Southeast Asia

Abstract. The variability in the hydroclimate over mainland Southeast Asia is strongly influenced by the El Niño–Southern Oscillation (ENSO) phenomenon, which has been linked to severe drought and floods that profoundly influence human societies and ecosystems alike. However, the spatial characteristics and long-term stationarity of ENSO's influence in the region are not well understood. We thus aim to analyse seasonal evolution and spatial variations in the effect of ENSO on precipitation over the period of 1980–2013, and long-term variation in the ENSO-teleconnection using tree-ring derived Palmer Drought Severity Indices (PDSI) that span from 1650–2004. We found that the majority of the study area is under the influence of ENSO, which has affected the region's hydroclimate over the majority (96 %) of the 355 year study period. Our results further indicate that there is a pattern of seasonal evolution of precipitation anomalies during ENSO. However, considerable variability in the ENSO's influence is revealed: the strength of ENSO's influence was found to vary in time and space, and the different ENSO events resulted in varying precipitation anomalies. Additional research is needed to investigate how this variation in ENSO teleconnection is influenced by other factors, such as the properties of the ENSO events and other ocean and atmospheric phenomena. In general, the high variability we found in ENSO teleconnection combined with limitations of current knowledge, suggests that the adaptation to extremes in hydroclimate in mainland Southeast Asia needs to go beyond "predict-and-control" and recognise both uncertainty and complexity as fundamental principles.

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Latin America's LNG market faces muted outlook

Emerald Expert Briefings ◽

10.1108/oxan-db221067 ◽

2017 ◽

Keyword(s):

Energy Source ◽

Oil And Gas ◽

Gas Production ◽

Liquefied Natural Gas ◽

Panama Canal ◽

Content Type ◽

Factors Affecting ◽

Production And Consumption ◽

Major Producer

Subject The outlook for the LNG market. Significance With major oil and gas reserves, and around 5% of global GDP, South America might in theory be expected to play an important role in the global liquefied natural gas (LNG) business. It both produces and consumes LNG, but the factors affecting LNG production and consumption are national and global rather than primarily regional. In global terms, the region is neither a major producer nor a large market. Impacts With no new LNG production or export facilities currently announced, the region will not become a major producer soon. The Panama Canal will play a key role in facilitating LNG trade around the region and globally. For countries lacking material gas production, for example Chile, LNG will continue to be a key energy source. Growing gas production in Brazil and Argentina over the medium to long term may increasingly relegate LNG consumption.

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