Climate changes in coastal areas of Patagonia: Observed trends and future projections

PESSACG N.; BLAZQUEZ J.; LANCELOTTI J.; SOLMAN S. A.

Global change in Atlantic coastal Patagonian ecosystems: A journey through time

Springer-Cham

Año: 2022; p. 13 - 42

Earths climate has warmed up since the 1950s and this climate change is unequivocal. The atmosphere and the oceans have warmed up, sea level has risen and snow pack and ice cover have declined (Stocker et al. 2013). These changes can clearly be attributed to the increase in anthropogenic greenhouse gases (Stocker et al. 2013). In addition to this, several studies carried out over the last decades have shown that global warming has a strong impact on continental and oceanic ecosystems and on their services to human beings (Hoegh-Guldberg et al. 2018). Changes in the climate system have impacted on coastal areas. The physical impacts on these zones can be divided into short and long time scale impacts (Wong et al. 2014). Floods, coastal erosion and coastal flooding, severe storms, and intense rainfall runoff are some of the physical impacts on coasts on a short time scale, while on longer time scales, the impacts are due to the effects of climate change on wind and waves patterns. Global warming can also modify climate variability in a region, which in turn modulates local climate by affecting storm frequency (intensity and location), wind patterns, and wave climate (such as wave height, meanor peak period and mean direction) (Wong et al. 2014) and related physical coastal processes (wave propagation, reflection, transmission, sediment transport) (Sierra and Casas-Prat 2014). These impacts on coastal areas are aggravated by human pressure associated with population growth trends in these areas. In many cases, human pressures may dominate over natural processes. As a consequence, coastal areas are influenced by human and climate drivers as well as by the complex interactions between them (Nicholls et al. 2007). Changes in the physical climate-drivers described above have been affecting the dynamics of biophysical and human systems in coastal areas of the region and future climate change is expected to further affect the ecosystem functioning and services. In particular, in the Atlantic coastal area of Patagonia which is the focus of this book- there are several examples of impacts described in detail in the next chapters of this book. In this context, the coastal systems could be considered as vulnerable to changes in climate.Within this frame of reference, the aim of this chapter is twofold. Firstly, to present the main characteristics of climate in continental Patagonian coastal regions and secondly, to describe the physical changes in atmospheric variables and climate patterns which in turn could lead to changes in the Atlantic coastal Patagonian ecosystems.The chapter is organized as follows: Section 2 describes climate characteristics in coastal areas of Patagonia including the main aspects of climate at regional and local scales and large-scale variability patterns. Section 3 consists in a review and analysis of the main observed climate trends and variability in coastal areas of Patagonia. Section 4 includes an evaluation of future climate projections in Patagonia with focus on coastal areas, followed by a synthesis and future perspectives in Section 5.