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Scholars have long debated whether international organizations (IO) matter in international politics. Skeptics argue that power politics determine outcomes while champions see IOs as important, independently shaping outcomes and reshaping the structure of politics. Between these extremes, scholars have made numerous theoretical and empirical contributions to understanding under what conditions IOs make a difference. Yet, the fundamental question remains: when IOs identify a significant problem, can they solve it? We identify an underutilized analytical approach to understanding this broad debate. Specifically, we suggest scholars analyze this question by focusing on an IOs response to given crises to provide internal validity to claims throughout this debate. Furthermore, we encourage scholars to move beyond the oft-cited global or European cases to better incorporate insights from IOs in various parts of the world. Here, we explore the Southern African Development Community's attempt to coordinate member states' maritime strategy to solve the emergent piracy problem caused by the Somali civil war. In identifying these new directions for research, we demonstrate that IOs, even under difficult circumstances, are effective actors in international politics. [ABSTRACT FROM AUTHOR]

Background and aim: Billfish are epipelagic marine predators facing increasing pressures such as overfishing and rising global temperatures. Overfishing is a major concern, as they are caught by industrial longline fishers targeting tuna. Billfish are targeted by multiple fishing sectors, which provides food, socio‐economic and cultural benefits. To support effective billfish management and conservation, it is essential to understand their spatial distribution and the environmental factors that may influence it. Location: The focus of this study is the Indian Ocean (IO), where there are gaps in understanding the interactions between fisheries and billfish distribution. Three of six billfish species are at risk from overfishing. Therefore, determining their distribution is crucial to their management and conservation. Methods: Using Ocean Biogeographic Information System (OBIS) occurrence data, Indian Ocean Tuna Commission (IOTC) catch data, and environmental covariates, we applied species distribution models to investigate the spatial extent of the realized niches of six billfish species in the IO. We also determined the role and relative importance of environmental drivers. Moreover, we evaluated the association between species' spatial distribution and the fishing effort distribution. Results: We found niche partitioning and overlap among the six species identified spatial distribution, with higher species richness in the northern region of the IO and off the East coast of Africa. Temperature, mixed layer depth and salinity were identified as the most important predictors of species distribution, with moderately warm and stable environments preferred by most billfish species. Areas with high species richness and high fishing effort overlap were primarily found in the Areas Beyond National Jurisdiction (ABNJ). In contrast, areas with high species diversity richness and low fishing effort were found mainly in the Exclusive Economic Zone (EEZ). Main conclusion: Spatial overlap between fishing effort and billfish projected distribution suggests inadvertent fishing pressure on billfish populations as they are caught together with targeted tuna. Spatial distribution transcends maritime zones, reinforcing a need to formulate effective management policies for marine areas beyond national jurisdictions. [ABSTRACT FROM AUTHOR]

In this study, we explore the possible mechanism of opposite ENSO effects on summer rainfall in the JJAS region (northern GHA) and autumn rainfall in the OND region (equatorial GHA). The two regions are identified based on the spatial distribution of high seasonal fractions of annual rainfall for the period 1979–2016. The summer rainfall over the JJAS region is negatively correlated with ENSO. It is because the warm Niño3.4 SST triggers zonal wave one pattern in tropics and forces upper-level westerly anomaly and the low-level easterly anomaly over tropical Africa. Thus, the weakened upper-level Tropical Easterly Jet (TEJ) and the low-level westerly over the JJAS region result in deficient rainfall during JJAS over the northern GHA. For the autumn rainfall variability over the equatorial GHA, IOD is a pivotal factor. But, autumn rainfall anomalies are far greater in ENSO and IOD coexisting years than those in IOD alone years. In other words, ENSO has a significant impact on the autumn rainfall over the equatorial GHA by means of IOD. It is because the warming SST, which is fully developed over western Indian Ocean (IO) in autumn of ENSO developing year, causes low-level convergence over the equatorial GHA and enhances upper-level easterly over tropical Africa. Those conditions are favorable for abundant rainfall over the equatorial GHA in autumn. [ABSTRACT FROM AUTHOR]

Most of current general circulation models (GCMs) show a remarkable positive precipitation bias over the southwestern equatorial Indian Ocean (SWEIO), which can be thought of as a westward expansion of the simulated IO convergence zone toward the coast of Africa. The bias is common to both coupled and uncoupled models, suggesting that its origin does not stem from the way boundary conditions are specified. The spatio-temporal evolution of the precipitation and associated three-dimensional atmospheric circulation biases is comprehensively characterized by comparing the GFDL AM3 atmospheric model to observations. It is shown that the oceanic bias, which develops in spring and reduces during the monsoon season, is associated to a consistent precipitation and circulation anomalous pattern over the whole Indian region. In the vertical, the areas are linked by an anomalous Hadley-type meridional circulation, whose northern branch subsides over northeastern India significantly affecting the monsoon evolution (e.g., delaying its onset). This study makes the case that the precipitation bias over the SWEIO is forced by the model excess response to the local meridional sea surface temperature (SST) gradient through enhanced near-surface meridional wind convergence. This is suggested by observational evidence and supported by AM3 sensitivity experiments. The latter show that relaxing the magnitude of the meridional SST gradient in the SWEIO can lead to a significant reduction of both local and large-scale precipitation and circulation biases. The ability of local anomalies over the SWEIO to force a large-scale remote response to the north is further supported by numerical experiments with the GFDL spectral dry dynamical core model. By imposing a realistic anomalous heating source over the SWEIO the model is able to reproduce the main dynamical features of the AM3 bias. These results indicate that improved GCM simulations of the South Asian summer monsoon could be achieved by reducing the springtime model bias over the SWEIO. Deficiencies in the atmospheric model, and in particular in the convective parameterization, are suggested to play a key role. Finally, the important mechanism controlling the simulated precipitation distribution over South Asia found here should be considered in the interpretation and attribution of regional precipitation variation under climate change. [ABSTRACT FROM AUTHOR]