Published online by Cambridge University Press: 19 June 2021
Recent estimates of global salt marsh area sit at 5.5 million hectares (Mcowen et al. 2017). Conservatively, this translates to $1 trillion of ecosystem services per annum, potentially as much as $5 trillion (De Groot et al. 2012, Mehvar et al. 2018), equivalent to the entire US federal budget for 2019. There can be little debate as to the value of salt marshes, both in terms of the ecosystem services they provide and the key part they play in helping us understand past climate and sea level trends. This chapter summarizes the preceding work and draws together some key observations and notable knowledge gaps highlighted in the previous chapters. We provide a focus on the expected response of salt marshes to the stresses created by a changing climate.