Abstract: The sub-Antarctic islands are remote and isolated environments with original flora and fauna composed of a few species that are highly adapted to cold oceanic conditions. Their peculiar naturalness makes these ecosystems intrinsically fragile.This book focuses on terrestrial ecosystems and, in particular, on invertebrates – earthworms, mollusks, spiders and insects – that inhabit the French sub-Antarctic islands of the South Indian Ocean. All native and introduced species are presented in the form of individual fact sheets, which include the main identification criteria, geographical distribution and principal ecological traits. Numerous summary tables, distribution maps of introduced species, and a discussion on the originality and vulnerability of this fauna are also included.The Terrestrial Macroinvertebrates of the Sub-Antarctic Iles Kerguelen and Ile de la Possession is based on an expansive literature base, as well as on observations and photographs taken as part of a research program funded by the French Polar Institute Paul-Emile Victor (IPEV). The book also gives an important part to the history of the discoveries of the different species, as well as current conservation issues.

Abstract: Mammals constitute a group of vertebrates that share a number of unique characteristics,such as nursing their young with milk, and having hair. The pattern of low mammal species diversity in the Arctic probably reflects a combination of mainly two driving factors: first, being homeotherms, mammals require a substantial amount of energy to sustain the various life processes, and the arctic regions are characterized by a very low availability of energy due to short seasons for primary production. Secondly, the occurrence of arctic mammals today reflects the reinvasion of the mammal species into the Arctic as the ecosystems were re-established following the deglaciation. This chapter discusses the characteristics of the arctic mammals, including their unique adaptations to life, and their role as both consumer and food base in the arctic ecosystems. Climate change in the Arctic may also alter the interactions within food webs.

Abstract: The accurate prediction of tides is vital for the operation of many industries, early warning of coastal flooding and scientific understanding of ocean processes. In this paper, we describe the creation method of a global dataset of tidal harmonics using NEMO (Nucleus for European Modelling of the Ocean) for the first time and an offline objective analysis scheme. Data are assimilated as part of a post-processing step, reducing the computational resources required. A reduced ensemble of tidal harmonics is generated, where each member is run for a shorter period of time than a central background state. This ensemble is used to estimate a single background covariance state, which is used for analysis. Output is validated using an ensemble of objective analyses. For each ensemble member, random selections of observations are omitted and validation is performed at these locations. Improvements in both Mean Absolute Error (MAE) and correlation coefficients (R2) are seen across all 6 of the largest diurnal and semi-diurnal constituents. MAEs in amplitude and phase are reduced by up to 78% and 89%, respectively, and correlations by as much as 0.14. In addition, the majority of locations (between 70 and 80%) see significant improvement.