Suppressing piracy in the early eighteenth century: pirates, merchants and British imperial authority in the Atlantic and Indian Oceans

Suppressing Piracy in the Early Eighteenth Century: Pirates, merchants and British imperial authority in the Atlantic and Indian Oceans

David Wilson. Suppressing Piracy in the Early Eighteenth Century: Pirates, Merchants and British Imperial Authority in the Atlantic and Indian Oceans. Woodbridge: Boydell Press, 2021. Pp. 312. $130.00 (cloth). - Volume 62 Issue 2

Book Review: <i>Suppressing Piracy in the Early Eighteenth Century: Pirates, Merchants and British Imperial Authority in the Atlantic and Indian Oceans</i> by David Wilson

Chaos reigns – at least in the historiography of the Raj. It was once the consensus among historians that British imperial authority in the Indian subcontinent was secure for at least the century-and-a-half before the Second World War. Recently, however, this narrative has drawn a range of challenges. Prominently, Mark Condos and Jon Wilson have held that British imperial authority was chronicallyinsecure. In their view, the irrational anxiety of generations of British officials produced a chaotic administration with minimal social purchase or ideological coherence. Instead of a confident state capable of acting as it chose, these historians have limned a psychologically embattled one incapable of acting except in the abstract, small scale, or short term. Their bold revision succeeds in dispelling the aura of indomitability that has often surrounded the Raj, and in directing attention to its overlooked discontents and weaknesses. Yet their characterization of the British regime asconstantlyandpervasivelyanxious is more an article of faith than a conclusion warranted by evidence. Nor do they explain how, if the regime suffered from permanent ‘chaos’ or ‘insecurity’, it managed to survive for some two hundred years. At the heart of Condos's and Wilson's approach is an effort to bypass texts that results, instead, in misreading them. It is largely by re-emphasizing rigorous textual methods, therefore, that Durba Ghosh offers a compelling alternative approach to the history of state vulnerability and disorder.

Abstract: Beginning in the early eighteenth century, a coherent body of racial policies emerged across the French Atlantic and Indian Oceans, targeting the socioeconomic status of people of non-European ancestry and restricting their right to marry or have sexual relations with French people. In addition to very specific local circumstances in the colonies, this coherent body of policies emerged because authorities attempted to standardize policies across the two oceans. The circulation of official correspondence and people on a transoceanic scale facilitated these changes. The scope of this standardization and circulation means that we cannot understand the full landscape of French racial discourse and policymaking unless we look at the Atlantic and Indian Oceans together. Yet the current historiography on race in the French colonies remains compartmentalized into smaller geographic units. Little work has been produced on race and racial policies for the French Indian Ocean, and the vast majority of publications on this topic have so far been produced by Atlantic specialists. Considering France's Atlantic and Indian Ocean colonies side by side demonstrates that racial policies in the Atlantic were shaped by developments in the Indian Ocean—and vice versa.

The impact of the Indian and Atlantic oceans variability on El Niño–Southern-Oscillation (ENSO) phenomenon is investigated through sensitivity experiments with the SINTEX-F2 coupled model. For each experiment, we suppressed the sea surface temperature (SST) variability in either the Indian or Atlantic oceans by applying a strong nudging of the SST toward a SST climatology computed either from a control experiment or observations. In the sensitivity experiments where the nudging is done toward a control SST climatology, the Pacific mean state and seasonal cycle are not changed. Conversely, nudging toward an observed SST climatology in the Indian or Atlantic domain significantly improves the mean state and seasonal cycle, not only in the nudged domain, but also in the whole tropics. These experiments also demonstrate that decoupling the Indian or Atlantic variability modifies the phase-locking of ENSO to the annual cycle, influences significantly the timing and processes of ENSO onset and termination stages, and, finally, shifts to lower frequencies the main ENSO periodicities. Overall, these results suggest that both the Indian and Atlantic SSTs have a significant damping effect on ENSO variability and promote a shorter ENSO cycle. The reduction of ENSO amplitude is particularly significant when the Indian Ocean is decoupled, but the shift of ENSO to lower frequencies is more pronounced in the Atlantic decoupled experiments. These changes of ENSO statistical properties are related to stronger Bjerknes and thermocline feedbacks in the nudged experiments. During the mature phase of El Niño events, warm SST anomalies are found over the Indian and Atlantic oceans in observations or the control run. Consistent with previous studies, the nudged experiments demonstrate that these warm SSTs induce easterly surface wind anomalies over the far western equatorial Pacific, which fasten the transition from El Niño to La Niña and promote a shorter ENSO cycle in the control run. These results may be explained by modulations of the Walker circulation induced directly or indirectly by the Indian and Atlantic SSTs. Another interesting result is that decoupling the Atlantic or Indian oceans change the timing of ENSO onset and the relative role of other ENSO atmospheric precursors such as the extra-tropical Pacific Meridional Modes or the Western North Pacific SSTs.

Oceanic differences in coral-bleaching responses to marine heatwaves

Abstract. The Atlantic Meridional Overturning Circulation (AMOC), an important circulation system that modulates the global climate, has been identified as a potential tipping element. To assess AMOC tipping, climate models are used that are known to have many biases, and it is unknown how these biases affect AMOC stability. We focus here on freshwater biases over the Indian and Atlantic oceans, as identified in CMIP6 models. Next, we use CLIMBER-X, an Earth system model of intermediate complexity (EMIC), to study the effect of biases in surface freshwater flux on AMOC tipping behavior. We introduce biases in the Indian and Atlantic oceans and perform hysteresis experiments where we slowly ramp up the surface freshwater forcing in the North Atlantic until the AMOC collapses; subsequently, the forcing is reversed until the AMOC recovers again. We find that negative (positive) biases in the Indian Ocean make the AMOC more unstable (stable), whereas negative (positive) biases in the Atlantic Ocean make the AMOC more stable (unstable). When biases are introduced in both the Atlantic and Indian oceans, the tipping point associated with the AMOC collapse is hardly affected. These results show that, if the freshwater bias we applied in the Indian Ocean is larger than the one applied in the Atlantic Ocean, the AMOC is more stable in CLIMBER-X. For more reliable assessments of AMOC tipping under future emission scenarios, (freshwater) bias reduction in climate models is therefore thought to be essential.

A global ocean model (ORCA2) forced with 50 yr of NCEP–NCAR reanalysis winds and heat fluxes has been used to investigate the evolution and forcing of interannual dipolelike sea surface temperature (SST) variability in the South Indian and South Atlantic Oceans. Although such patterns may also exist at times in only one of these basins and not the other, only events where there are coherent signals in both basins during the austral summer have been chosen for study in this paper. A positive (negative) event occurs when there is a significant warm (cool) SST anomaly evident in the southwest of both the South Indian and South Atlantic Oceans and a cool (warm) anomaly in the eastern subtropics. The large-scale forcing of these events appears to consist of a coherent modulation of the wavenumber-3 or -4 pattern in the Southern Hemisphere atmospheric circulation such that the semipermanent subtropical anticyclone in each basin is shifted from its summer mean position and its strength is modulated. A relationship to the Antarctic Oscillation is also apparent, and seems to strengthen after the mid-1970s. The modulated subtropical anticyclones lead to changes in the tropical easterlies and midlatitude westerlies in the South Atlantic and South Indian Oceans that result in anomalies in latent heat fluxes, upwelling, and Ekman heat transports, all of which contribute to the SST variability. In addition, there are significant modulations to the strong Rossby wave signals in the South Indian Ocean. The results of this study confirm the ability of the ORCA2 model to represent these dipole patterns and indicate connections between large-scale modulations of the Southern Hemisphere midlatitude atmospheric circulation and coevolving SST variability in the South Atlantic and South Indian Oceans.

This study has utilized spectral analysis to ascertain the nature of decadal rainfall variability, while correlation, singular value decomposition (SVD), and composite analyses were employed to explore and understand the possible associated mechanisms. Inferences were drawn to the interannual timescales. The spectrum analysis of October to December (OND) rainfall revealed dominant signals at 2.4, 2.9, and 5.0, and a band near 16–25 years. These cyclicities suggest that dominant drivers of Tanzania rainfall anomalies evolve on interannual and decadal timescales. Interannual variations in Tanzania rainfall are mostly linked to the Indian and Pacific oceans. Significant sea surface temperature (SST) anomalies in the Indian and Pacific oceans included those associated with Indian Ocean Dipole (IOD) and El Niño‐Southern Oscillations (ENSO), respectively and are linked to changes in the atmospheric circulation anomalies over the western Indian Ocean. The observed circulation variations are most likely to influence Tanzania rainfall. In contrast, wet and dry decades are mostly linked to the Indian and Atlantic oceans. The Indian ocean provides stronger teleconnections with Tanzania rainfall at decadal timescales, consistent with interannual timescales teleconnections. Notably, the ‘dipole’ like forcing observed at interannual timescales is less coherent at decadal timescales over the Indian Ocean. As such, the Indian Ocean displayed a coherent monopole pattern in decadal SST. As a result of these differences, the location of the western Indian ocean centre of convection activities observed at interannual timescales has shifted to around the central Indian Ocean at decadal timescales. Wet decades in Tanzania rainfall are associated with the condition of enhanced convection and increase moisture content centred over the central Indian Ocean. This convective condition was observed to spread to a large area of the Indian Ocean and the African continent, including the study area.

It is well established that plate-tectonic processes operate on a global scale and that spatially separate but temporally coincident events may be linked. However, identifying such links in the geological record and understanding the mechanisms involved remain speculative. This is particularly acute during major geodynamic events, such as the dispersal of supercontinents, where multiple axes of breakup may be present as well as coincidental collisional events. To explore this aspect of plate tectonics, we present a detailed analysis of the temporal variation in the mean half rate of seafloor spreading in the Indian and Atlantic Oceans, as well as plate-kinematic attributes extracted from global plate-tectonic models during the dispersal of Gondwana since ca. 200 Ma. Our analysis shows that during the ~20 m.y. prior to collision between India and Asia at ca. 55 Ma, there was an increase in the mean rate of seafloor spreading in the Indian Ocean. This manifests as India rapidly accelerating toward Asia. This event was then followed by a prompt deceleration in the mean rate of Indian Ocean seafloor spreading after India collided with Asia at ca. 55 Ma. Since inception, the mean rate of seafloor spreading in the Indian Ocean has been generally greater than that in the Atlantic Ocean, and the period of fastest mean half spreading rate in the Indian Ocean was coincident with a slowdown in mean half seafloor spreading rate in the competing Atlantic Ocean. We hypothesize that faster and hotter seafloor spreading in the Indian Ocean resulted in larger ridge-push forces, which were transmitted through the African plate, leading to a slowdown in Atlantic Ocean spreading. Following collision between India and Asia, and a slowdown of Indian Ocean spreading, Atlantic spreading rates consequently increased again. We conclude that the processes in the Indian and Atlantic Oceans have likely remained coupled throughout their existence, that their individual evolution has influenced each other, and that, more generally, spreading in one basin inevitably influences proximal regions. While we do not believe that ridge push is the main cause of plate motions, we consider it to have played a role in the coupling of the kinematic evolution of these oceans. The implication of this observation is that interaction and competition between nascent ocean basins and ridges during supercontinent dispersal exert a significant control on resultant continental configuration.

Secular variation of Nd and Pb isotopes in ferromanganese crusts from the Atlantic, Indian and Pacific Oceans

ABSTRACTClimatic variability significantly impacts global fisheries by altering oceanographic conditions, potentially affecting fishing yields and species composition, and studying climate change's effects is crucial for understanding marine ecosystems, predicting disruptions and informing sustainable management strategies. Hence, this study examined the impact of climatic variability on pelagic predators like tunas, marlins and swordfish, using fishery data from 2005, January to 2016, December, focusing on nine commercially significant species each from the Indian and South Atlantic oceans. The hypothesis of the study was composed of two parts, that is, different populations of same species in the Indian and South Atlantic Ocean may respond differently to climatic variability, and the impact of teleconnections on fisheries may vary across these two oceans. The first part of the current study involved evaluating the importance of climatic variability on species using generalised additive modelling, while the second part involved analysing the unique effects of species‐specific climatic variability using cross‐spectral and cross‐wavelet analysis. The current study revealed two significant findings: firstly, species in the Indian Ocean and South Atlantic Ocean had distinct response to climatic variability (first hypothesis), and secondly, the species in the Indian Ocean displayed a higher level of sensitivity to teleconnection impacts (second hypothesis). The study's findings can help fisheries communities to anticipate and adapt to changes in fish distribution and productivity, enhancing their practices and spatial management, thereby promoting sustainable global fisheries management.

&amp;lt;p&amp;gt;The predictability of El Ni&amp;amp;#241;o and La Ni&amp;amp;#241;a is investigated. In this case, the recently discovered so-called Global Atmospheric Oscillation (GAO) is considered (Serykh et al., 2019). Assuming GAO to be the main mode of short-term climatic variability, this study defines an index that characterizes the dynamics and relationships of the extratropical components of the GAO and El Ni&amp;amp;#241;o &amp;amp;#8211; Southern Oscillation (ENSO). Due to the general propagation of the GAO&amp;amp;#8217;s spatial structure from west to east, another index &amp;amp;#8211; predictor of ENSO is defined. The cross-wavelet analysis between both of these indices and the Oceanic Ni&amp;amp;#241;o Index (ONI) is performed. This analysis reveals a range of timescales within which the closest relationship between the GAO and ONI takes place. Using this relationship, it is possible to predict El Ni&amp;amp;#241;o and La Ni&amp;amp;#241;a with a lead-time of approximately 12 months (Serykh and Sonechkin, 2020a).&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;Using data on the distribution of temperatures in the Pacific, Indian, and Atlantic Oceans, large-scale structures of spatial and temporal variations of these temperatures are investigated (Serykh and Sonechkin, 2020b). A structure is found which is almost identical to the spatial and temporal sea surface temperature (SST) structure that is characteristic of the GAO. Variations in water temperature in a near-equatorial zone of the Pacific Ocean at depths up to about 150 meters behave themselves in the same way as variations in sea surface height and SST. At even greater depths, variations in water temperature reveal a &amp;quot;striped&amp;quot; structure, which is, however, overall similar to that of SST variations. Variations of water temperature at depths in all three oceans spread from east to west along the equator with a period of 14 months. This makes it possible to think that the dynamics of these temperatures are controlled by the so-called Pole tides. The surface North Pacific Pole Tide was found previously responsible for excitation of El Ni&amp;amp;#241;o (Serykh and Sonechkin, 2019). The deep Pole tides in the Southern Atlantic and Southern Indian Ocean appear to be triggers of the Atlantic El Ni&amp;amp;#241;o and Indian Ocean Dipole (IOD). Thus, IOD manifests itself at the depth of the thermocline more clearly than on the surface of the Indian Ocean. The out-of-phase behavior of El Ni&amp;amp;#241;o and IOD is explained by the 180-degree difference in the longitudes of these phenomena.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;&amp;amp;#160;&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;References&amp;lt;/strong&amp;gt;&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;Serykh I.V., Sonechkin D.M. Nonchaotic and globally synchronized short-term climatic variations and their origin // Theoretical and Applied Climatology. 2019. Vol. 137. No. 3-4. pp 2639&amp;amp;#8211;2656. https://doi.org/10.1007/s00704-018-02761-0&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;Serykh I.V., Sonechkin D.M., Byshev V.I., Neiman V.G., Romanov Yu.A. Global Atmospheric Oscillation: An Integrity of ENSO and Extratropical Teleconnections // Pure and Applied Geophysics. 2019. Vol. 176. pp 3737&amp;amp;#8211;3755. https://doi.org/10.1007/s00024-019-02182-8&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;Serykh I.V., Sonechkin D.M. El Ni&amp;amp;#241;o forecasting based on the global atmospheric oscillation // International Journal of Climatology. 2020a. https://doi.org/10.1002/joc.6488&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;Serykh I.V., Sonechkin D.M. Interrelations between temperature variations in oceanic depths and the Global atmospheric oscillation // Pure and Applied Geophysics. 2020b. Vol. 177.&amp;amp;#160;pp 5951&amp;amp;#8211;5967. https://doi.org/10.1007/s00024-020-02615-9&amp;lt;/p&amp;gt;

&amp;lt;p&amp;gt;Ocean-atmosphere interactions in the tropics have a profound influence on the climate system. El Ni&amp;amp;#241;o&amp;amp;#8211;Southern Oscillation (ENSO), which is spawned in the tropical Pacific, is the most prominent and well-known year-to-year variation on Earth. Its reach is global, and its impacts on society and the environment are legion. Because ENSO is so strong, it can excite other modes of climate variability in the Indian Ocean by altering the general circulation of the atmosphere. However, ocean-atmosphere interactions internal to the Indian Ocean are capable of generating distinct modes of climate variability as well. Whether the Indian Ocean can feedback onto Atlantic and Pacific climate has been an on-going matter of debate. We are now beginning to realize that the tropics, as a whole, are a tightly inter-connected system, with strong feedbacks from the Indian and Atlantic Oceans onto the Pacific. These two-way interactions affect the character of ENSO and Pacific decadal variability and shed new light on the recent hiatus in global warming.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;Here we review advances in our understanding of pantropical interbasins climate interactions with the Indian Ocean and their implications for both climate prediction and future climate projections. ENSO events force changes in the Indian Ocean than can feed back onto the Pacific. Along with reduced summer monsoon rainfall over the Indian subcontinent, a developing El Ni&amp;amp;#241;o can trigger a positive Indian Ocean Dipole (IOD) in fall and an Indian Ocean Basinwide (IOB) warming in winter and spring. Both IOD and IOB can feed back onto ENSO. For example, a positive IOD can favor the onset of El Ni&amp;amp;#241;o, and an El Ni&amp;amp;#241;o&amp;amp;#8211;forced IOB can accelerate the demise of an El Ni&amp;amp;#241;o and its transition to La Ni&amp;amp;#241;a. These tropical interbasin linkages however vary on decadal time scales. Warming during a positive phase of Atlantic Multidecadal Variability over the past two decades has strengthened the Atlantic forcing of the Indo-Pacific, leading to an unprecedented intensification of the Pacific trade winds, cooling of the tropical Pacific, and warming of the Indian Ocean. These interactions forced from the tropical Atlantic were largely responsible for the recent hiatus in global surface warming.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;Climate modeling studies to address these issues are unfortunately compromised by pronounced systematic errors in the tropics that severely suppress interactions with the Indian and Pacific Oceans. As a result, there could be considerable uncertainty in future projections of Indo-Pacific climate variability and the background conditions in which it is embedded. Projections based on the current generation of climate models suggest that Indo-Pacific mean-state changes will involve slower warming in the eastern than in the western Indian Ocean. Given the presumed strength of the Atlantic influence on the pantropics, projections of future climate change could be substantially different if systematic model errors in the Atlantic were corrected. There is hence tremendous potential for improving seasonal to decadal climate predictions and for improving projections of future climate change in the tropics though advances in our understanding of the dynamics that govern interbasin linkages.&amp;lt;/p&amp;gt;