Статті в журналах: "Western tropical Atlantic"

1

Brown, Wendell, William Johns, Eli Katz, Kevin Leaman, Julian McCreary, Robert Molinari, Philip Richardson, and Claus Rooth. "A Western Tropical Atlantic Experiment (WESTRAX)." Oceanography 5, no. 1 (1992): 73–77. http://dx.doi.org/10.5670/oceanog.1992.38.

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2

Zhang, Gan, and Zhuo Wang. "North Atlantic Rossby Wave Breaking during the Hurricane Season: Association with Tropical and Extratropical Variability." Journal of Climate 32, no. 13 (June 6, 2019): 3777–801. http://dx.doi.org/10.1175/jcli-d-18-0299.1.

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Abstract This study explores the connection of Rossby wave breaking (RWB) with tropical and extratropical variability during the Atlantic hurricane season. The exploration emphasizes subtropical anticyclonic RWB events over the western North Atlantic, which strongly affect tropical cyclone (TC) activity. The first part of the study investigates the link between RWB and tropical sea surface temperature (SST) variability. Tropical SST variability affects tropical precipitation and modulates the large-scale atmospheric circulation over the subtropical Atlantic, which influences the behaviors of Rossby waves and the frequency of RWB occurrence. Meanwhile, RWB regulates surface heat fluxes and helps to sustain SST anomalies in the western North Atlantic. The second part of the study explores the connections between RWB and extratropical atmosphere variability by leveraging weather regime analysis. The weather regimes over the North Atlantic are closely associated with RWB over the eastern North Atlantic and western Europe, but show weak associations with RWB over the western North Atlantic. Instead, RWB over the western basin is closely related to the weather regimes in the North Pacific–North America sector. The finding helps clarify why the correlation between the Atlantic TC activity and the summertime North Atlantic Oscillation is tenuous. The relations between the extratropical weather regimes and tropical climate modes are also discussed. The findings suggest that both tropical and extratropical variability are important for understanding variations of RWB events and their impacts on Atlantic TC activity.

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3

Oliva, Frank, Andre E. Viau, Matthew C. Peros, and Marc Bouchard. "Paleotempestology database for the western North Atlantic basin." Holocene 28, no. 10 (June 22, 2018): 1664–71. http://dx.doi.org/10.1177/0959683618782598.

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Paleotempestology, the study of past tropical cyclone activity, has grown considerably over the past two decades, and there is now a relatively dense network of sites across the Western North Atlantic Basin providing records of past tropical cyclone variability. This paper presents a new database of paleotempestological records generated from 61 studies published between 1993 and 2018 for this region. A total of 266 data entries, consisting of the calibrated ages of individual tropical cyclone events and the boundaries of ‘active’ tropical cyclone periods from the present to 8000 cal. yr BP, along with the site names, geographic coordinates, proxy indicator(s) used, materials upon which dating was undertaken, and information about the depositional basin type (e.g. lagoon, mangrove), are included in the database for each site. The database is housed at the National Oceanographic and Atmospheric Association (NOAA) ( https://www.ncdc.noaa.gov/paleo/study/21391 ) and is available for free download. This publicly available database will permit a greater number of researchers to work on questions related to past tropical cyclone dynamics and more easily allow studies of long-term spatial-temporal tropical cyclone relationships to be undertaken.

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4

Miranda, Daniele de A., Juliana Leonel, Jonathan P. Benskin, Jana Johansson, and Vanessa Hatje. "Perfluoroalkyl Substances in the Western Tropical Atlantic Ocean." Environmental Science & Technology 55, no. 20 (October 7, 2021): 13749–58. http://dx.doi.org/10.1021/acs.est.1c01794.

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5

Chen, Tsing-Chang, Shih-Yu Wang, Ming-Cheng Yen, and Adam J. Clark. "Are Tropical Cyclones Less Effectively Formed by Easterly Waves in the Western North Pacific than in the North Atlantic?" Monthly Weather Review 136, no. 11 (November 1, 2008): 4527–40. http://dx.doi.org/10.1175/2008mwr2149.1.

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Abstract It has been observed that the percentage of tropical cyclones originating from easterly waves is much higher in the North Atlantic (∼60%) than in the western North Pacific (10%–20%). This disparity between the two ocean basins exists because the majority (71%) of tropical cyclogeneses in the western North Pacific occur in the favorable synoptic environments evolved from monsoon gyres. Because the North Atlantic does not have a monsoon trough similar to the western North Pacific that stimulates monsoon gyre formation, a much larger portion of tropical cyclogeneses than in the western North Pacific are caused directly by easterly waves. This study also analyzed the percentage of easterly waves that form tropical cyclones in the western North Pacific. By carefully separating easterly waves from the lower-tropospheric disturbances generated by upper-level vortices that originate from the tropical upper-tropospheric trough (TUTT), it is observed that 25% of easterly waves form tropical cyclones in this region. Because TUTT-induced lower-tropospheric disturbances often become embedded in the trade easterlies and resemble easterly waves, they have likely been mistakenly identified as easterly waves. Inclusion of these “false” easterly waves in the “true” easterly wave population would result in an underestimation of the percentage of easterly waves that form tropical cyclones, because the TUTT-induced disturbances rarely stimulate tropical cyclogenesis. However, an analysis of monsoon gyre formation mechanisms over the western North Pacific reveals that 82% of monsoon gyres develop through a monsoon trough–easterly wave interaction. Thus, it can be inferred that 58% (i.e., 82% × 71%) of tropical cyclones in this region are an indirect result of easterly waves. Including the percentage of tropical cyclones that form directly from easterly waves (∼25%), it is found that tropical cyclones formed directly and indirectly from easterly waves account for over 80% of tropical cyclogeneses in the western North Pacific. This is more than the percentage that has been documented by previous studies in the North Atlantic.

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6

Zhang, Chidong, John M. Wallace, Robert A. Houze, Edward J. Zipser, and Kerry A. Emanuel. "Relocation of GATE from the Pacific to the Atlantic." Bulletin of the American Meteorological Society 103, no. 8 (August 2022): E1991—E1999. http://dx.doi.org/10.1175/bams-d-21-0151.1.

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Abstract This article documents historically the planning of the Global Atmospheric Research Program’s (GARP) Atlantic Tropical Experiment (GATE), the largest atmospheric field program of all time. In its earliest planning, GATE was called the Tropical Meteorological Experiment (TROMEX) and was designed to be in the tropical western Pacific. For reasons including concerns of the U.S. Department of Defense, the international project was relocated to the tropical Atlantic and renamed GATE.

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7

Costa, Monica F., and Mário Barletta. "Microplastics in coastal and marine environments of the western tropical and sub-tropical Atlantic Ocean." Environmental Science: Processes & Impacts 17, no. 11 (2015): 1868–79. http://dx.doi.org/10.1039/c5em00158g.

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8

Foltz, Gregory R., Karthik Balaguru, and Samson Hagos. "Interbasin Differences in the Relationship between SST and Tropical Cyclone Intensification." Monthly Weather Review 146, no. 3 (March 2018): 853–70. http://dx.doi.org/10.1175/mwr-d-17-0155.1.

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Sea surface temperature (SST) is one of the most important parameters for tropical cyclone (TC) intensification. Here, it is shown that the relationship between SST and TC intensification varies considerably from basin to basin, with SST explaining less than 4% of the variance in TC intensification rates in the Atlantic, 12% in the western North Pacific, and 23% in the eastern Pacific. Several factors are shown to be responsible for these interbasin differences. First, variability of SST along TCs’ tracks is lower in the Atlantic. This is due to smaller horizontal SST gradients in the Atlantic, compared to the Pacific, and stronger damping of prestorm SST’s contribution to TC intensification by the storm-induced cold SST wake in the Atlantic. The damping occurs because SST tends to vary in phase with TC-induced SST cooling: in the Gulf of Mexico and northwestern Atlantic, where SSTs are highest, TCs tend to be strongest and their translations slowest, resulting in the strongest storm-induced cooling. The tendency for TCs to be more intense over the warmest SST in the Atlantic also limits the usefulness of SST as a predictor since stronger storms are less likely to experience intensification. Finally, SST tends to vary out of phase with vertical wind shear and outflow temperature in the western Pacific. This strengthens the relationship between SST and TC intensification more in the western Pacific than in the eastern Pacific or Atlantic. Combined, these factors explain why prestorm SST is such a poor predictor of TC intensification in the Atlantic, compared to the eastern and western North Pacific.

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9

Yang, Haijun, and Lu Wang. "Tropical Oceanic Response to Extratropical Thermal Forcing in a Coupled Climate Model: A Comparison between the Atlantic and Pacific Oceans*." Journal of Climate 24, no. 15 (August 1, 2011): 3850–66. http://dx.doi.org/10.1175/2011jcli3927.1.

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Abstract The tropical oceanic response to the extratropical thermal forcing is quantitatively estimated in a coupled climate model. This work focuses on comparison of the responses between the tropical Atlantic and Pacific. Under the same extratropical forcing, the tropical sea surface temperature responses are comparable. However, the responses in the tropical subsurface in the two oceans are distinct. The tropical subsurface response in the Atlantic can be twice of that in the Pacific. The maximum subsurface temperature change in the tropical Pacific occurs in the eastern lower thermocline, while that in the tropical Atlantic occurs in the west and well below the lower thermocline. The different responses in the tropical Atlantic and Pacific are closely related to the different changes in the meridional overturning circulations. The Pacific shallow overturning circulation, or the subtropical cell, tends to slow down (speed up) in response to the extratropical warming (cooling) forcing. The changes in the upwelling in the eastern equatorial Pacific as well as the shallow subduction from the extratropical southern Pacific along the eastern boundary are accountable for the eastern Pacific temperature change. The Atlantic overturning circulation consists of the shallow subtropical cell and the deep thermohaline circulation. A weakened thermohaline circulation will result in a strengthened northern subtropical cell, in which the change in the lower branch, or the low-latitude North Brazil Current, can cause strong response below the western tropical thermocline. Here the coastal Kelvin wave along the western boundary on the intermediate isopycnal level also plays an important role in the equatorward conveying of the climate anomalies in the mid-to-high-latitude Atlantic, particularly during the initial stage of the extratropical forcing.

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10

Álvarez-García, Francisco J., María J. OrtizBevia, and William D. CabosNarvaez. "On the Structure and Teleconnections of North Atlantic Decadal Variability." Journal of Climate 24, no. 9 (May 1, 2011): 2209–23. http://dx.doi.org/10.1175/2011jcli3478.1.

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Abstract Decadal variability in the North Atlantic has been associated in the literature with a tripolar pattern of sea surface temperature (SST) anomalies that show one sign in the western midlatitudinal North Atlantic and the opposite in the subpolar and tropical North Atlantic. The present analysis of observed SST from 1870 to 2009 leads to the dissection of the SST tripole into two components, each with a different time scale in the decadal band and different teleconnections in the Atlantic basin; while the subpolar and tropical poles present quasi-decadal variations with a period of about 9 years, essentially uncorrelated with other parts of the basin, the center of action in the western midlatitudes is characterized by a longer time scale of about 14 years and significant correlations with the tropical South Atlantic and the Norwegian and North Sea(s). The 9-yr period variations are associated with an atmospheric configuration resembling the east Atlantic pattern, whereas the 14-yr period fluctuations seem to be related to the North Atlantic Oscillation pattern. Each component also bears a different relationship with the decadal variability in the Pacific Ocean.

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11

Montoya, J. P., M. Voss, and D. G. Capone. "Spatial variation in N<sub>2</sub>-fixation rate and diazotroph activity in the Tropical Atlantic." Biogeosciences Discussions 3, no. 6 (November 9, 2006): 1739–61. http://dx.doi.org/10.5194/bgd-3-1739-2006.

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Abstract. A variety of N2-fixers occur in the tropical Atlantic and these diazotrophs make a substantial contribution to the nitrogen budget of the upper water column. A synthesis of previously published and novel rate measurements for the Tropical North Atlantic provides insight into the role of two different diazotroph groups in supporting N2 fixation in the tropical Atlantic. The overall rate of N2-fixation by the two groups of diazotrophs was similar in the eastern and western parts of the basin, but N2-fixation by \\textit{Trichodesmium} was strongly dominant in the western part of the basin while small diazotrophs played a much larger role to the east of 40° W. The reasons for this shift in dominance are unclear, as is the identity of the small organisms fixing N2 in the water column.

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12

Richardson, Susan L. "Biogeography of epiphytic foraminiferans in the tropical Western Atlantic." Anuário do Instituto de Geociências 29, no. 1 (January 1, 2006): 564–66. http://dx.doi.org/10.11137/2006_1_564-566.

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13

Molinari, Robert L., and Elizabeth Johns. "Upper layer temperature structure of the western tropical Atlantic." Journal of Geophysical Research 99, no. C9 (1994): 18225. http://dx.doi.org/10.1029/94jc01204.

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14

Pailler, K., B. Bourlès, and Y. Gouriou. "The barrier layer in the western tropical Atlantic Ocean." Geophysical Research Letters 26, no. 14 (July 15, 1999): 2069–72. http://dx.doi.org/10.1029/1999gl900492.

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15

Lefévre, Nathalie, Denis Diverrés, and Francis Gallois. "Origin of CO2 undersaturation in the western tropical Atlantic." Tellus B: Chemical and Physical Meteorology 62, no. 5 (January 1, 2010): 595–607. http://dx.doi.org/10.1111/j.1600-0889.2010.00475.x.

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16

Emanuel, Kerry. "Environmental Factors Affecting Tropical Cyclone Power Dissipation." Journal of Climate 20, no. 22 (November 15, 2007): 5497–509. http://dx.doi.org/10.1175/2007jcli1571.1.

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Abstract Revised estimates of kinetic energy production by tropical cyclones in the Atlantic and western North Pacific are presented. These show considerable variability on interannual-to-multidecadal time scales. In the Atlantic, variability on time scales of a few years and more is strongly correlated with tropical Atlantic sea surface temperature, while in the western North Pacific, this correlation, while still present, is considerably weaker. Using a combination of basic theory and empirical statistical analysis, it is shown that much of the variability in both ocean basins can be explained by variations in potential intensity, low-level vorticity, and vertical wind shear. Potential intensity variations are in turn factored into components related to variations in net surface radiation, thermodynamic efficiency, and average surface wind speed. In the Atlantic, potential intensity, low-level vorticity, and vertical wind shear strongly covary and are also highly correlated with sea surface temperature, at least during the period in which reanalysis products are considered reliable. In the Pacific, the three factors are not strongly correlated. The relative contributions of the three factors are quantified, and implications for future trends and variability of tropical cyclone activity are discussed.

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17

González, José A., and Manuel Biscoito. "First record of the deep-sea stomatopod Bathysquilla microps (Manning, 1961) (Stomatopoda, Bathysquillidae) from the eastern Atlantic Ocean." Crustaceana 88, no. 12-14 (2015): 1301–6. http://dx.doi.org/10.1163/15685403-00003495.

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In the present account Bathysquilla microps (Manning, 1961) is recorded for the first time from the West African coast off Morocco and the Western Sahara. In the Atlantic Ocean, this species was only known from the tropical western basin; therefore this is the first time it is recorded from the eastern Atlantic.

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18

King, Martin P., and Fred Kucharski. "Observed Low-Frequency Covariabilities between the Tropical Oceans and the North Atlantic Oscillation in the Twentieth Century." Journal of Climate 19, no. 6 (March 15, 2006): 1032–41. http://dx.doi.org/10.1175/jcli3677.1.

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Abstract The low-frequency covariabilities of tropical sea surface temperature (SST) and the North Atlantic Oscillation (NAO) during twentieth-century winters are investigated by maximum covariance analysis (MCA) using reanalysis data. It was found that the positive NAO phase is positively correlated to an increase in tropical SST, especially during the recent decades. The western tropical Pacific SST displays high correlation with the NAO throughout the whole of the twentieth century. For this ocean region, the MCA homogeneous map has a SST spatial pattern with meridional gradients. It was also found that a cooling of tropical Atlantic SST is correlated with positive NAO. The influence of the tropical Atlantic SST on the NAO is strongest during the pre-1960s period.

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19

Olán-González, Manuel, Héctor Reyes-Bonilla, Lorenzo Álvarez-Filip, Horacio Pérez-España, and Damien Olivier. "Fish diversity divergence between tropical eastern pacific and tropical western Atlantic coral reefs." Environmental Biology of Fishes 103, no. 11 (September 23, 2020): 1323–41. http://dx.doi.org/10.1007/s10641-020-01026-y.

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20

Gao, Si, Zhifan Chen, and Wei Zhang. "Impacts of Tropical North Atlantic SST on Western North Pacific Landfalling Tropical Cyclones." Journal of Climate 31, no. 2 (January 2018): 853–62. http://dx.doi.org/10.1175/jcli-d-17-0325.1.

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This study examines the impacts of tropical North Atlantic (TNA) sea surface temperature anomaly (SSTA) on western North Pacific (WNP) landfalling tropical cyclones (TCs). The authors find that TNA SSTA has significant negative correlations with the frequency of TCs making landfall in China, Vietnam, the Korean Peninsula and Japan, and the entirety of East Asia. TNA SSTA influences the frequency of TC landfalls in these regions by regulating TC genesis location and frequency associated with modulated environmental conditions. During cold TNA SST years, larger low-level relative vorticity and weaker vertical wind shear lead to more TC formations over the South China Sea (SCS) and western Philippine Sea (WPS), and larger low-level relative vorticity, higher midlevel relative humidity, and weaker vertical wind shear result in more TC formations over the eastern part of WNP (EWNP). More TCs forming over different regions are important for more TC landfalls in Vietnam (mainly forming over the SCS and WPS), south China (predominantly forming over the SCS), Taiwan (mostly forming over the WPS), and the Korean Peninsula and Japan (forming over the WPS and EWNP). Tracks of these landfalling TCs basically follow the mean steering flow in spite of different directions of steering flow anomalies in the vicinity. The modulation of large-scale environments by TNA SSTA may be through two possible pathways proposed in previous studies: the Indian Ocean relaying effect and the subtropical eastern Pacific relaying effect. The results of this study suggest that TNA SSTA is a potential predictor for the frequency of TCs making landfall in China, Vietnam, the Korean Peninsula and Japan, and the entirety of East Asia.

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21

Cotrim da Cunha, L., and E. T. Buitenhuis. "Riverine influence on the tropical Atlantic Ocean biogeochemistry." Biogeosciences Discussions 9, no. 2 (February 17, 2012): 1945–69. http://dx.doi.org/10.5194/bgd-9-1945-2012.

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Abstract. We assess the role of riverine inputs of N, Si, Fe, organic and inorganic C in the tropical Atlantic Ocean using a global ocean biogeochemistry model. We use two sensitivity tests to investigate the role of the western (South American Rivers) and eastern (African Rivers) riverine nutrient inputs on the tropical Atlantic Ocean biogeochemistry (between 20° S–20° N and 70° W–20°). Increased nutrient availability from river inputs in this area (compared to an extreme scenario with no river nutrients) leads to an increase in 14 % (0.7 Pg C a−1) in open ocean primary production (PP), and 21 % (0.2 Pg C a−1) in coastal ocean PP. We estimate very modest increases in open and coastal ocean export production and sea-air CO2 fluxes. Results suggest that in the tropical Atlantic Ocean, the large riverine nutrient inputs on the western side have a larger impact on primary production and sea-air CO2 exchanges. On the other hand, African river inputs, although smaller than South American inputs, have larger impact on the coastal and open tropical Atlantic Ocean export production. This is probably due to a combination of nutrient trapping in upwelling areas off the Congo River outflow, and differences in delivered nutrient ratios leading to alleviation in limitation conditions mainly for diatoms.

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22

Prince, Kevin C., and Clark Evans. "A Climatology of Indirect Tropical Cyclone Interactions in the North Atlantic and Western North Pacific Basins." Monthly Weather Review 148, no. 10 (October 1, 2020): 4035–59. http://dx.doi.org/10.1175/mwr-d-19-0377.1.

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AbstractWhile it is understood that a recurving tropical cyclone (TC) that interacts with the midlatitude flow can cause large changes to the midlatitude flow pattern, it is much less understood if, and how, such events could impact a downstream tropical cyclone. Here, an indirect TC interaction is defined as one in which a primary TC perturbs the downstream midlatitude waveguide within one synoptic-scale wavelength of a secondary TC. In this study, a climatology and composite analysis using ERA-Interim reanalysis data is completed for all indirect interactions occurring between two tropical and/or subtropical cyclones in the North Atlantic and western North Pacific basins between 1989 and 2018. In all, 26 cases are identified in the North Atlantic and 56 cases are identified in the western North Pacific. The composite-mean interaction between a primary TC and upstream trough amplifies the immediate downstream ridge, increasing the tropospheric-deep vertical wind shear on its poleward and, in the western North Pacific, eastern, and equatorward flanks. An amplified downstream trough is detectable farther downstream in the western North Pacific 1–2 days after interaction onset; however, the same is not true in the North Atlantic, in which some cases exhibit anticyclonic Rossby wave breaking of the immediate downstream ridge. Secondary TCs that weaken following the indirect-interaction events are primarily located along the gradient between the downstream ridge and trough (North Atlantic) or at high latitudes (western North Pacific); those that strengthen are primarily located equatorward of the downstream ridge, particularly in the western North Pacific.

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23

Pisera, Andrzej, and Shirley A. Pomponi. "New data on lithistid sponges from the deep Florida shelf with description of a new species of Theonella." Journal of the Marine Biological Association of the United Kingdom 95, no. 7 (February 18, 2015): 1297–309. http://dx.doi.org/10.1017/s0025315414001477.

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Most lithistids occur worldwide in deep-water environments, but can be found in some places in shallow water. They are not well known in the tropical western Atlantic, despite the fact that they were first described in the late 1800s. We report here two species of poorly known theonellid demosponges (Astrophorina), Discodermia dissoluta and Theonella atlantica, and one new species, Theonella wrightae, from the north-west, south-west and south Florida shelf. There is considerable variability in habitus, colour and spiculation in this species. If samples are taken randomly from different specimens and from functionally and structurally different locations on the sponge, the specimens could be mistakenly identified or individuals of the same species could be described as different species. This report increases the number of lithistid sponges reported from the tropical western Atlantic region to 30 species, but our unpublished data suggest a much higher number of species present in this region. It is also the second report of the relatively deep-water (81 m) occurrence of D. dissoluta that is mostly known from depths as shallow as 10–30 m.

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24

Yu, Wei, Weiqing Han, and David Gochis. "Influence of the Madden–Julian Oscillation and Intraseasonal Waves on Surface Wind and Convection of the Tropical Atlantic Ocean." Journal of Climate 25, no. 23 (December 1, 2012): 8057–74. http://dx.doi.org/10.1175/jcli-d-11-00528.1.

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Abstract Atmospheric intraseasonal variability in the tropical Atlantic is analyzed using satellite winds, outgoing longwave radiation (OLR), and reanalysis products during 2000–08. The analyses focus on assessing the effects of dominant intraseasonal atmospheric convective processes, the Madden–Julian oscillation (MJO), and Rossby waves on surface wind and convection of the tropical Atlantic Ocean and African monsoon area. The results show that contribution from each process varies in different regions. In general, the MJO events dominate the westward-propagating Rossby waves in affecting strong convection in the African monsoon region. The Rossby waves, however, have larger contributions to convection in the western Atlantic Ocean. Both the westward- and eastward-propagating signals contribute approximately equally in the central Atlantic basin. The effects of intraseasonal signals have evident seasonality. Both convection amplitude and the number of strong convective events associated with the MJO are larger during November–April than during May–October in all regions. Convection associated with Rossby wave events is stronger during November–April for all regions, and the numbers of Rossby wave events are higher during November–April than during May–October in the African monsoon region, and are comparable for the two seasons in the western and central Atlantic basins. Of particular interest is that the MJOs originating from the Indo-Pacific Ocean can be enhanced over the tropical Atlantic Ocean while they propagate eastward, amplifying their impacts on the African monsoon. On the other hand, Rossby waves can originate either in the eastern equatorial Atlantic or West African monsoon region, and some can strengthen while they propagate westward, affecting surface winds and convection in the western Atlantic and Central American regions.

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25

Roopnarine, Peter D. "A history of diversification, extinction, and invasion in tropical America as derived from species-level phylogenies of chionine genera (Family Veneridae)." Journal of Paleontology 75, no. 3 (May 2001): 644–57. http://dx.doi.org/10.1017/s0022336000039706.

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Phylogenetic reconstructions of two tropical American venerid genera, Chione and Chionopsis (subfamily Chioninae) were attempted at the species-level. The purposes of the analyses were to provide historical reconstructions of origination and extinction events in the two clades, as well as patterns of invasion and diversification. The analyses were based entirely on conchological characters to facilitate the inclusion of a substantial number of fossil taxa, but difficulties were encountered due to the quality of preservation and availability of material. Nevertheless the two genera were established as monophyletic clades, and the reconstructions yielded considerable insight into their histories in tropical America. The analyses suggest that both genera originated in the tropical western Atlantic, Chionopsis by at least the early Oligocene, and Chione in the early Miocene. Various branches of both genera subsequently invaded the tropical eastern Pacific several times prior to Seaway closure, with only one possible reciprocal invasion of the western Atlantic. Pliocene extinction affected both genera more significantly in the western Atlantic relative to the eastern Pacific, and diversity is higher today in the latter region. These conclusions are not entirely consistent with the fossil records of the genera, but this incongruency highlights the need for much more extensive sampling of the eastern Pacific Cenozoic record.

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26

Roopnarine, Peter D. "A history of diversification, extinction, and invasion in tropical America as derived from species-level phylogenies of chionine genera (Family Veneridae)." Journal of Paleontology 75, no. 5 (September 2001): 644–57. http://dx.doi.org/10.1017/s0022336000039846.

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Phylogenetic reconstructions of two tropical American venerid genera, Chione and Chionopsis (subfamily Chioninae) were attempted at the species-level. The purposes of the analyses were to provide historical reconstructions of origination and extinction events in the two clades, as well as patterns of invasion and diversification. The analyses were based entirely on conchological characters to facilitate the inclusion of a substantial number of fossil taxa, but difficulties were encountered due to the quality of preservation and availability of material. Nevertheless the two genera were established as monophyletic clades, and the reconstructions yielded considerable insight into their histories in tropical America. The analyses suggest that both genera originated in the tropical western Atlantic, Chionopsis by at least the early Oligocene, and Chione in the early Miocene. Various branches of both genera subsequently invaded the tropical eastern Pacific several times prior to Seaway closure, with only one possible reciprocal invasion of the western Atlantic. Pliocene extinction affected both genera more significantly in the western Atlantic relative to the eastern Pacific, and diversity is higher today in the latter region. These conclusions are not entirely consistent with the fossil records of the genera, but this incongruency highlights the need for much more extensive sampling of the eastern Pacific Cenozoic record.

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27

Bieli, Melanie, Adam H. Sobel, Suzana J. Camargo, and Michael K. Tippett. "A Statistical Model to Predict the Extratropical Transition of Tropical Cyclones." Weather and Forecasting 35, no. 2 (February 26, 2020): 451–66. http://dx.doi.org/10.1175/waf-d-19-0045.1.

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Abstract This paper introduces a logistic regression model for the extratropical transition (ET) of tropical cyclones in the North Atlantic and the western North Pacific, using elastic net regularization to select predictors and estimate coefficients. Predictors are chosen from the 1979–2017 best track and reanalysis datasets, and verification is done against the tropical/extratropical labels in the best track data. In an independent test set, the model skillfully predicts ET at lead times up to 2 days, with latitude and sea surface temperature as its most important predictors. At a lead time of 24 h, it predicts ET with a Matthews correlation coefficient of 0.4 in the North Atlantic, and 0.6 in the western North Pacific. It identifies 80% of storms undergoing ET in the North Atlantic and 92% of those in the western North Pacific. In total, 90% of transition time errors are less than 24 h. Select examples of the model’s performance on individual storms illustrate its strengths and weaknesses. Two versions of the model are presented: an “operational model” that may provide baseline guidance for operational forecasts and a “hazard model” that can be integrated into statistical TC risk models. As instantaneous diagnostics for tropical/extratropical status, both models’ zero lead time predictions perform about as well as the widely used cyclone phase space (CPS) in the western North Pacific and better than the CPS in the North Atlantic, and predict the timings of the transitions better than CPS in both basins.

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28

Berg, Robert J., and Lixion A. Avila. "Atlantic Hurricane Season of 2009." Monthly Weather Review 139, no. 4 (April 2011): 1049–69. http://dx.doi.org/10.1175/2010mwr3476.1.

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The 2009 Atlantic season was marked by below-average tropical cyclone activity with the formation of nine tropical storms, the fewest since the 1997 Atlantic hurricane season. Of these, three became hurricanes and two strengthened into major hurricanes (category 3 or higher on the Saffir–Simpson Hurricane Wind Scale). In addition, there were two tropical depressions that did not reach storm strength. The numbers of tropical storms and hurricanes were below the long-term averages of 11 named storms and 6 hurricanes, although the number of major hurricanes equaled the long-term average of 2. Many of the cyclones remained relatively weak. Only one tropical cyclone, Tropical Storm Claudette, made landfall in the United States, although Ida affected the northern Gulf Coast as a tropical storm before moving inland as an extratropical cyclone. Hurricane Bill and Tropical Storm Danny indirectly affected the East Coast by producing high surf, rip currents, and beach erosion; Bill also produced tropical storm conditions over Bermuda and parts of Atlantic Canada. Hurricane Ida made landfall in Nicaragua and also affected parts of Honduras, the Yucatan Peninsula of Mexico, and western Cuba. Tropical Storm Erika had minor effects on the northern Leeward Islands, mainly in the form of light rain, and Tropical Storm Grace moved through the Azores with little impact. The death toll from the 2009 Atlantic tropical cyclones was six. A verification of National Hurricane Center official forecasts during 2009 is also presented. Official track errors and forecast skill set records for accuracy at lead times between 24 and 72 h. Official intensity forecast errors were mostly larger than the previous 5-yr means, although intensity forecast skill was at or above historical highs since the intensity skill baseline [i.e., Decay-Statistical Hurricane Intensity Forecast model version 5 (Decay-SHIFOR5)] errors were well above average.

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29

Rodrigues, Regina R., Reindert J. Haarsma, Edmo J. D. Campos, and Tércio Ambrizzi. "The Impacts of Inter–El Niño Variability on the Tropical Atlantic and Northeast Brazil Climate." Journal of Climate 24, no. 13 (July 1, 2011): 3402–22. http://dx.doi.org/10.1175/2011jcli3983.1.

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Abstract In this study, observations and numerical simulations are used to investigate how different El Niño events affect the development of SST anomalies in the Atlantic and how this relates to the Brazilian northeast (NE) precipitation. The results show that different types of El Niño have different impacts on the SST anomalies of the equatorial and tropical South Atlantic but a similar SST response in the tropical North Atlantic. Strong and long (weak and short) El Niños with the main heating source located in the eastern (central) Pacific generate cold (warm) anomalies in the cold tongue and Benguela upwelling regions during boreal winter and spring. When the SST anomalies in the eastern equatorial and tropical South Atlantic are cold (warm), the meridional SST gradient across the equator is positive (negative) and the ITCZ is not allowed (allowed) to move southward during the boreal spring; as a consequence, the precipitation is below (above) the average over the NE. Thus, strong and long (weak and short) El Niños are followed by dry (wet) conditions in the NE. During strong and long El Niños, changes in the Walker circulation over the Atlantic and in the Pacific–South Atlantic (PSA) wave train cause easterly wind anomalies in the western equatorial Atlantic, which in turn activate the Bjerknes mechanism, establishing the cold tongue in boreal spring and summer. These easterly anomalies are also responsible for the Benguela upwelling. During short and weak El Niños, westerly wind anomalies are present in the western equatorial Atlantic accompanied by warm anomalies in the eastern equatorial and tropical South Atlantic; a positive phase of the South Atlantic dipole develops during boreal winter. The simulations highlight the importance of ocean dynamics in establishing the correct slope of the equatorial thermocline and SST anomalies, which in turn determine the correct rainfall response over the NE.

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30

Wang, Chunzai, and David B. Enfield. "A Further Study of the Tropical Western Hemisphere Warm Pool." Journal of Climate 16, no. 10 (May 15, 2003): 1476–93. http://dx.doi.org/10.1175/1520-0442-16.10.1476.

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Abstract Variability of the tropical Western Hemisphere warm pool (WHWP) of water warmer than 28.5°C, which extends seasonally over parts of the eastern North Pacific, the Gulf of Mexico, the Caribbean, and the western tropical North Atlantic (TNA), was previously studied by Wang and Enfield using the da Silva data from 1945–93. Using additional datasets of the NCEP–NCAR reanalysis field and the NCEP SST from 1950–99, and the Levitus climatological subsurface temperature, the present paper confirms and extends the previous study of Wang and Enfield. The WHWP alternates with northern South America as the seasonal heating source for the Walker and Hadley circulations in the Western Hemisphere. During the boreal winter a strong Hadley cell emanates northward from the Amazon heat source with subsidence over the subtropical North Atlantic north of 20°N, sustaining a strong North Atlantic anticyclone and associated northeast (NE) trade winds over its southern limb in the TNA. This circulation, including the NE trades, is weakened during Pacific El Niño winters and results in a spring warming of the TNA, which in turn induces the development of an unusually large summer warm pool and a wetter Caribbean rainy season. As the WHWP develops in the late boreal spring, the center of tropospheric heating and convection shifts to the WHWP region, whence the summer Hadley circulation emanates from the WHWP and forks into the subsidence regions of the subtropical South Atlantic and South Pacific. During the summers following El Niño, when the warm pool is larger than normal, the increased Hadley flow into the subtropical South Pacific reinforces the South Pacific anticyclone and trade winds, probably playing a role in the transition back to the cool phase of ENSO. Seasonally, surface heat fluxes seem to be primarily responsible for warming of the WHWP. Interannually, all of the datasets suggest that a positive ocean–atmosphere feedback through longwave radiation and associated cloudiness seems to operate in the WHWP. During the winter preceding a large warm pool, there is a strong weakening of the Hadley cell that serves as a “tropospheric bridge” for transferring El Niño effects to the Atlantic sector and inducing warming of the warm pool. Associated with the warm SST anomalies is a decrease in sea level pressure anomalies and an anomalous increase in atmospheric convection and cloudiness. The increase in convective activity and cloudiness results in less longwave radiation loss from the sea surface, which then reinforces SST anomalies. This data-inferred hypothesis of the longwave radiation feedback process needs to be further investigated for its validation in the WHWP.

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31

Johnson, Nathaniel C., Lakshmi Krishnamurthy, Andrew T. Wittenberg, Baoqiang Xiang, Gabriel A. Vecchi, Sarah B. Kapnick, and Salvatore Pascale. "The Impact of Sea Surface Temperature Biases on North American Precipitation in a High-Resolution Climate Model." Journal of Climate 33, no. 6 (March 15, 2020): 2427–47. http://dx.doi.org/10.1175/jcli-d-19-0417.1.

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AbstractPositive precipitation biases over western North America have remained a pervasive problem in the current generation of coupled global climate models. These biases are substantially reduced, however, in a version of the Geophysical Fluid Dynamics Laboratory Forecast-Oriented Low Ocean Resolution (FLOR) coupled climate model with systematic sea surface temperature (SST) biases artificially corrected through flux adjustment. This study examines how the SST biases in the Atlantic and Pacific Oceans contribute to the North American precipitation biases. Experiments with the FLOR model in which SST biases are removed in the Atlantic and Pacific are carried out to determine the contribution of SST errors in each basin to precipitation statistics over North America. Tropical and North Pacific SST biases have a strong impact on northern North American precipitation, while tropical Atlantic SST biases have a dominant impact on precipitation biases in southern North America, including the western United States. Most notably, negative SST biases in the tropical Atlantic in boreal winter induce an anomalously strong Aleutian low and a southward bias in the North Pacific storm track. In boreal summer, the negative SST biases induce a strengthened North Atlantic subtropical high and Great Plains low-level jet. Each of these impacts contributes to positive annual mean precipitation biases over western North America. Both North Pacific and North Atlantic SST biases induce SST biases in remote basins through dynamical pathways, so a complete attribution of the effects of SST biases on precipitation must account for both the local and remote impacts.

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32

Zhang, Dongxiao, Michael J. McPhaden, and William E. Johns. "Observational Evidence for Flow between the Subtropical and Tropical Atlantic: The Atlantic Subtropical Cells*." Journal of Physical Oceanography 33, no. 8 (August 1, 2003): 1783–97. http://dx.doi.org/10.1175/2408.1.

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Abstract This study determines the mean pathways and volume transports in the pycnocline and surface layer for water flowing between the subtropical and tropical Atlantic Ocean, using potential vorticity, salinity, geostrophic flow maps on isopycnal surfaces, and surface drifter velocities. In both hemispheres, subducted salinity maximum waters flow into the Tropics in the pycnocline along both interior and western boundary pathways. The North Atlantic ventilating trajectories are confined to densities between about 23.2 and 26.0 σθ, and only about 2 Sv (Sv ≡ 106 m3 s–1) of water reaches the Tropics through the interior pathway, whereas the western boundary contributes about 3 Sv to the equatorward thermocline flow. Flow on shallower surfaces of this density range originates from the central Atlantic near 40°W between 12° and 16°N whereas flow on the deeper surfaces originates from near 20°W just off the coast of Africa at higher latitudes. The pathways skirt around the potential vorticity barrier located under the intertropical convergence zone and reach their westernmost location at about 10°N. In the South Atlantic, about 10 Sv of thermocline water reaches the equator through the combination of interior (4 Sv) and western boundary (6 Sv) routes in a slightly higher density range than in the North Atlantic. Similar to the North Atlantic, the shallower layers originate in the central part of the basin (along 10°–30°W at 10°–15°S) and the deeper layers originate at higher latitudes from the eastern part of the basin. However, the ventilation pathways are spread over a much wider interior window in the Southern Hemisphere than in the Northern Hemisphere that at 6°S extends from 10°W to the western boundary. The equatorward convergent flows in the thermocline upwell into the surface layer and return to the subtropics through surface poleward divergence. As much as 70% of the tropical Atlantic upwelling into the surface layer is associated with these subtropical circulation cells, with the remainder contributed by the warm return flow of the large-scale thermohaline overturning circulation.

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33

Haarsma, Reindert J., Edmo Campos, Wilco Hazeleger, and Camiel Severijns. "Influence of the Meridional Overturning Circulation on Tropical Atlantic Climate and Variability." Journal of Climate 21, no. 6 (March 15, 2008): 1403–16. http://dx.doi.org/10.1175/2007jcli1930.1.

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Abstract The influence of the meridional overturning circulation on tropical Atlantic climate and variability has been investigated using the atmosphere–ocean coupled model Speedy-MICOM (Miami Isopycnic Coordinate Ocean Model). In the ocean model MICOM the strength of the meridional overturning cell can be regulated by specifying the lateral boundary conditions. In case of a collapse of the basinwide meridional overturning cell the SST response in the Atlantic is characterized by a dipole with a cooling in the North Atlantic and a warming in the tropical and South Atlantic. The cooling in the North Atlantic is due to the decrease in the strength of the western boundary currents, which reduces the northward advection of heat. The warming in the tropical Atlantic is caused by a reduced ventilation of water originating from the South Atlantic. This effect is most prominent in the eastern tropical Atlantic during boreal summer when the mixed layer attains its minimum depth. As a consequence the seasonal cycle as well as the interannual variability in SST is reduced. The characteristics of the cold tongue mode are changed: the variability in the eastern equatorial region is strongly reduced and the largest variability is now in the Benguela, Angola region. Because of the deepening of the equatorial thermocline, variations in the thermocline depth in the eastern tropical Atlantic no longer significantly affect the mixed layer temperature. The gradient mode remains unaltered. The warming of the tropical Atlantic enhances and shifts the Hadley circulation. Together with the cooling in the North Atlantic, this increases the strength of the subtropical jet and the baroclinicity over the North Atlantic.

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34

Ballantine, David L., and Michael J. Wynne. "Platysiphonia and Apoglossum (Delesseriaceae, Rhodophyta) in the tropical western Atlantic." Phycologia 24, no. 4 (December 1985): 459–65. http://dx.doi.org/10.2216/i0031-8884-24-4-459.1.

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35

Ballantine, David L., Hideo Ohba, Chad Lozada-Troche, and Hector Ruiz. "Boergesenia parvulasp. nov. (Siphonocladales, Chlorophyta) from the Tropical Western Atlantic." Cryptogamie, Algologie 32, no. 4 (November 2011): 327–36. http://dx.doi.org/10.7872/crya.v32.iss4.2011.327.

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36

Suca, Justin J., Leif K. Rasmuson, Estrella Malca, Trika Gerard, and John T. Lamkin. "Characterizing larval swordfish habitat in the western tropical North Atlantic." Fisheries Oceanography 27, no. 3 (January 7, 2018): 246–58. http://dx.doi.org/10.1111/fog.12249.

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37

Bezrukov, Yu F. "Hydrologic structure of waters in the north-western Tropical Atlantic." Soviet Journal of Physical Oceanography 1, no. 3 (May 1990): 211–18. http://dx.doi.org/10.1007/bf02196874.

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38

Bonou, Frédéric Kpèdonou, Carlos Noriega, Nathalie Lefèvre, and Moacyr Araujo. "Distribution of CO2 parameters in the Western Tropical Atlantic Ocean." Dynamics of Atmospheres and Oceans 73 (March 2016): 47–60. http://dx.doi.org/10.1016/j.dynatmoce.2015.12.001.

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39

Varona, H. L., D. Veleda, M. Silva, M. Cintra, and M. Araujo. "Amazon River plume influence on Western Tropical Atlantic dynamic variability." Dynamics of Atmospheres and Oceans 85 (March 2019): 1–15. http://dx.doi.org/10.1016/j.dynatmoce.2018.10.002.

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40

Bub, Frank L., and Wendell S. Brown. "Intermediate layer water masses in the western tropical Atlantic Ocean." Journal of Geophysical Research: Oceans 101, no. C5 (May 15, 1996): 11903–22. http://dx.doi.org/10.1029/95jc03372.

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41

Fernandes, Katia, Walter Baethgen, Sergio Bernardes, Ruth DeFries, David G. DeWitt, Lisa Goddard, Waldo Lavado, et al. "North Tropical Atlantic influence on western Amazon fire season variability." Geophysical Research Letters 38, no. 12 (June 2011): n/a. http://dx.doi.org/10.1029/2011gl047392.

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42

Littler, D. S., and M. M. Littler. "Systematics of Avrainvillea (Bryopsidales, Chlorophyta) in the tropical western Atlantic." Phycologia 31, no. 5 (September 1992): 375–418. http://dx.doi.org/10.2216/i0031-8884-31-5-375.1.

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43

Leão de Moura, Rodrigo, Matheus Oliveira Freitas, Ronaldo Bastos Francini-Filho, and Carolina Viviana Minte-Vera. "Spawning patterns of commercially important reef fish (Lutjanidae and Serranidae) in the tropical western South Atlantic." Scientia Marina 75, no. 1 (February 4, 2011): 135–46. http://dx.doi.org/10.3989/scimar.2011.75n1135.

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44

O’Reilly, Christopher H., Tim Woollings, Laure Zanna, and Antje Weisheimer. "The Impact of Tropical Precipitation on Summertime Euro-Atlantic Circulation via a Circumglobal Wave Train." Journal of Climate 31, no. 16 (August 2018): 6481–504. http://dx.doi.org/10.1175/jcli-d-17-0451.1.

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The influence of tropical precipitation variability on summertime seasonal circulation anomalies in the Euro-Atlantic sector is investigated. The dominant mode of the maximum covariance analysis (MCA) between the Euro-Atlantic circulation and tropical precipitation reveals a cyclonic anomaly over the extratropical North Atlantic, contributing to anomalously wet conditions over western Europe and dry conditions over eastern Europe and Scandinavia (in the positive phase). The related mode of tropical precipitation variability is associated with tropical Pacific SST anomalies and is closely linked to the El Niño–Southern Oscillation (ENSO). The second MCA mode consists of weaker tropical precipitation anomalies but with a stronger extratropical signal that reflects internal atmospheric variability. The teleconnection mechanism is tested in barotropic model simulations, which indicate that the observed link between the dominant mode of tropical precipitation and the Euro-Atlantic circulation anomalies is largely consistent with linear Rossby wave dynamics. The barotropic model response consists of a circumglobal wave train in the extratropics that is primarily forced by divergence anomalies in the eastern tropical Pacific. Both the eastward and westward group propagation of the Rossby waves are found to be important in determining the circulation response over the Euro-Atlantic sector. The mechanism was also analyzed in an operational seasonal forecasting system, ECMWF’s System 4. While System 4 is well able to reproduce and skillfully forecast the tropical precipitation, the extratropical circulation response is absent over the Euro-Atlantic region, which is likely related to biases in the Asian jet stream.

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45

Ventrice, Michael J., Christopher D. Thorncroft, and Carl J. Schreck. "Impacts of Convectively Coupled Kelvin Waves on Environmental Conditions for Atlantic Tropical Cyclogenesis." Monthly Weather Review 140, no. 7 (July 1, 2012): 2198–214. http://dx.doi.org/10.1175/mwr-d-11-00305.1.

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Abstract High-amplitude convectively coupled equatorial atmospheric Kelvin waves (CCKWs) are explored over the tropical Atlantic during the boreal summer (1989–2009). Focus is given to the atmospheric environmental conditions that are important for tropical cyclogenesis. CCKWs are characterized by deep westerly vertical wind shear to the east of its convectively active phase and easterly vertical wind shear to the west of it. This dynamical signature increases vertical wind shear over the western tropical Atlantic ahead of the convectively active phase, and reduces vertical wind shear after its passage. The opposite is true over the eastern tropical Atlantic where the climatological vertical wind shear is easterly. Positive total column water vapor (TCWV) anomalies progress eastward with the convectively active phase of the CCKW, whereas negative TCWV anomalies progress eastward with the convectively suppressed phase. During the passage of the convectively active phase of the CCKW, a zonally oriented strip of low-level cyclonic relative vorticity is generated over the tropical Atlantic. Two days later, this strip becomes more wavelike and moves back toward the west. This signature resembles a train of westward-moving easterly waves and suggests CCKWs may influence such events. Strong CCKWs over the tropical Atlantic tend to occur during the decay of the active convection associated with the Madden–Julian oscillation over the Pacific. This relationship could be used to provide better long-range forecasts of tropical convective patterns and Atlantic tropical cyclogenesis.

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46

Castellanos, P., E. J. D. Campos, J. Piera, O. T. Sato, and M. A. F. Silva Dias. "Impacts of Agulhas Leakage on the Tropical Atlantic Western Boundary Systems." Journal of Climate 30, no. 17 (September 2017): 6645–59. http://dx.doi.org/10.1175/jcli-d-15-0878.1.

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The influx of warmer and saltier Indian Ocean waters into the Atlantic—the Agulhas leakage—is now recognized to play an important role in the global thermohaline circulation and climate. In this study the results of a ⅞° simulation with the Hybrid Coordinate Ocean Model, which exhibit an augmentation in the Agulhas leakage, is investigated. This increase in the leakage ought to have an impact on the meridional oceanic volume and heat transports in the Atlantic Ocean. Significant linear trends found in the integrated transport at 20°, 15°, and 5°S correlate well with decadal fluctuations of the Agulhas leakage. The augmented transport also seems to be related to an increase in the latent heat flux observed along the northeastern coastline of Brazil since 2003. This study shows that the precipitation on the Brazilian coast has been increasing since 2005, at the same location and with the same regime shift observed for the latent heat flux and the volume transport. This suggests that the increase of the Agulhas transport affects the western boundary system of the tropical Atlantic Ocean, which is directly related to an increase in the precipitation and latent heat flux along the western coast.

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47

Bell, Ray, Kevin Hodges, Pier Luigi Vidale, Jane Strachan, and Malcolm Roberts. "Simulation of the Global ENSO–Tropical Cyclone Teleconnection by a High-Resolution Coupled General Circulation Model." Journal of Climate 27, no. 17 (August 28, 2014): 6404–22. http://dx.doi.org/10.1175/jcli-d-13-00559.1.

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Abstract This study assesses the influence of the El Niño–Southern Oscillation (ENSO) on global tropical cyclone activity using a 150-yr-long integration with a high-resolution coupled atmosphere–ocean general circulation model [High-Resolution Global Environmental Model (HiGEM); with N144 resolution: ~90 km in the atmosphere and ~40 km in the ocean]. Tropical cyclone activity is compared to an atmosphere-only simulation using the atmospheric component of HiGEM (HiGAM). Observations of tropical cyclones in the International Best Track Archive for Climate Stewardship (IBTrACS) and tropical cyclones identified in the Interim ECMWF Re-Analysis (ERA-Interim) are used to validate the models. Composite anomalies of tropical cyclone activity in El Niño and La Niña years are used. HiGEM is able to capture the shift in tropical cyclone locations to ENSO in the Pacific and Indian Oceans. However, HiGEM does not capture the expected ENSO–tropical cyclone teleconnection in the North Atlantic. HiGAM shows more skill in simulating the global ENSO–tropical cyclone teleconnection; however, variability in the Pacific is overpronounced. HiGAM is able to capture the ENSO–tropical cyclone teleconnection in the North Atlantic more accurately than HiGEM. An investigation into the large-scale environmental conditions, known to influence tropical cyclone activity, is used to further understand the response of tropical cyclone activity to ENSO in the North Atlantic and western North Pacific. The vertical wind shear response over the Caribbean is not captured in HiGEM compared to HiGAM and ERA-Interim. Biases in the mean ascent at 500 hPa in HiGEM remain in HiGAM over the western North Pacific; however, a more realistic low-level vorticity in HiGAM results in a more accurate ENSO–tropical cyclone teleconnection.

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48

Paterne, Martine, Nathalie Feuillet, Guy Cabioch, Elsa Cortijo, Dominique Blamart, Jennifer Weill-Accardo, Lucile Bonneau, Christophe Colin, Eric Douville, and Edwige Pons-Branchu. "Reservoir Ages in the Western Tropical North Atlantic from One Coral off Martinique Island (Lesser Antilles)." Radiocarbon 60, no. 2 (April 2018): 639–52. http://dx.doi.org/10.1017/rdc.2017.118.

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AbstractSea surface reservoir ages (R) are reported from radiocarbon (14C) measurements of the annual growth bands of coral Siderastrea siderea collected on the Atlantic coast off Martinique Island, in the Lesser Antilles volcanic arc. Mean values of R are similar between 1835 and 1845 during pre-anthropogenic times at 385±30 yr and between 1895 and 1905 at 382±20 yr when there was a huge eruption from the Montagne Pelée volcano in 1902–1903. Limited 14C aging of sea surface (~40 yr) may be due to enhanced volcanic activity. Variability of R is slightly greater during 1835–1845 than during 1895–1905. It is linked to a moderate increase of ∆14C of 5‰, strengthened by a clear increase of δ18O of 0.4‰. This is attributed to a decrease of the northward advection of the South Atlantic Waters into the western tropical North Atlantic and Caribbean Sea and relative enhanced westward flux of the tropical North Atlantic surface waters, the southern waters having lower values of 14C and δ18O than the North Atlantic ones. From 1835 to 1845, the fraction of the South Atlantic Waters transported up to Martinique Island was reduced from 25% to 15%.

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49

TAYLOR, JOHN D., EMILY A. GLOVER, LISA SMITH, CHIHO IKEBE, and SUZANNE T. WILLIAMS. "New molecular phylogeny of Lucinidae: increased taxon base with focus on tropical Western Atlantic species (Mollusca: Bivalvia)." Zootaxa 4196, no. 3 (November 23, 2016): 381. http://dx.doi.org/10.11646/zootaxa.4196.3.2.

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A new molecular phylogeny of the Lucinidae using 18S and 28S rRNA and cytochrome b genes includes many species from the tropical Western Atlantic as well as additional taxa from the Indo-West Pacific. This study provides a phylogenetic framework for a new taxonomy of tropical Western Atlantic lucinids. The analysis confirmed five major clades—Pegophyseminae, Leucosphaerinae, Myrteinae, Codakiinae and Lucininae, with Monitilorinae and Fimbriinae represented by single species. The Leucosphaerinae are expanded and include Callucina winckworthi and the W. Atlantic Myrtina pristiphora that groups with several Indo-West Pacific Myrtina species. Within the Codakiinae two abundant species of Ctena from the Western Atlantic with similar shells are discriminated as C. orbiculata and C. imbricatula, while in the Indo-West Pacific Ctena bella is a probable species complex. The Lucininae is the most species rich and disparate subfamily with several subclades apparent. Three species of Lucina are recognized in the W. Atlantic L. aurantia, L. pensylvanica and L. roquesana. Pleurolucina groups near to Cavilinga and Lucina, while Lucinisca muricata is more closely related to the E. Pacific L. fenestrata than to the Atlantic L. nassula. A new species of Parvilucina is identified from molecular analyses having been confounded with Parvilucina pectinata but differs in ligament structure. Also, the former Parvilucina clenchi is more distant and assigned to Guyanella.

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50

Zhang, Gan, Zhuo Wang, Melinda S. Peng, and Gudrun Magnusdottir. "Characteristics and Impacts of Extratropical Rossby Wave Breaking during the Atlantic Hurricane Season." Journal of Climate 30, no. 7 (April 2017): 2363–79. http://dx.doi.org/10.1175/jcli-d-16-0425.1.

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This study investigates the characteristics of extratropical Rossby wave breaking (RWB) during the Atlantic hurricane season and its impacts on Atlantic tropical cyclone (TC) activity. It was found that RWB perturbs the wind and moisture fields throughout the troposphere in the vicinity of a breaking wave. When RWB occurs more frequently over the North Atlantic, the Atlantic main development region (MDR) is subject to stronger vertical wind shear and reduced tropospheric moisture; the basinwide TC counts are reduced, and TCs are generally less intense, have a shorter lifetime, and are less likely to make landfalls. A significant negative correlation was found between Atlantic TC activity and RWB occurrence during 1979–2013. The correlation is comparable to that with the MDR SST index and stronger than that with the Niño-3.4 index. Further analyses suggest that the variability of RWB occurrence in the western Atlantic is largely independent of that in the eastern Atlantic. The RWB occurrence in the western basin is more closely tied to the environmental variability of the tropical North Atlantic and is more likely to hinder TC intensification or reduce the TC lifetime because of its proximity to the central portion of TC tracks. Consequently, the basinwide TC counts and the accumulated cyclone energy have a strong correlation with western-basin RWB occurrence but only a moderate correlation with eastern-basin RWB occurrence. The results highlight the extratropical impacts on Atlantic TC activity and regional climate via RWB and provide new insights into the variability and predictability of TC activity.

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