Chapter 12
Oceanic Planetary Waves and Eddies:
A Privileged View from Satellite Altimetry
Paolo Cipollini, Anna C. S. Sutcliffe, and Ian S. Robinson
12.1 Introduction
Satellite altimetry allows sustained observations of a wide range of ocean dynamics, from features spanning just a few tens of km to the mean global sea level
spatially, and from a few days to decades temporally, with profound repercussions on our knowledge of the oceans and how they affect climate. Amongst the
many success stories for altimetry, one particularly dear to ocean dynamicists is the
systematic detection, characterization and tracking of large- and meso-scale propagating features, virtually ubiquitous in the world’s oceans, and their classification
as either planetary waves or eddies, which has involved significant efforts by several research groups. In this chapter we review (in Section 12.3) the main results of
these efforts, and highlight the important implications that those findings have had
on our understanding of how the ocean works. We also discuss (in Section 12.4)
several intriguing questions that have been prompted by the satellite-based observations of propagating features – sometimes challenging the previous knowledge
based on insufficient experimental data, other times opening completely new paths
of investigation into scientifically uncharted waters. But first we start (in Section
12.2) with a brief explanation of the importance of propagating systems for oceans
and climate.
12.2 The Importance of Oceanic Propagating Features
Oceans play a crucial role in the Earth’s climate system and in mediating its response
to the present radiative forcing imbalance, especially at the longer time scales.
Ocean dynamics can be divided into a variety of components, each of which can
be considered individually at its own scale, but it is important to keep in mind that
it is the interactions between all the components at different scales that makes the
P. Cipollini (B)
Ocean Observing and Climate Research Group, National Oceanography Centre,
Southampton SO14 3ZH, UK
e-mail: cipo@noc.soton.ac.uk
195
V. Barale et al. (eds.), Oceanography from Space,
DOI 10.1007/978-90-481-8681-5_12, C
Springer Science+Business Media B.V. 2010
Oceanic Planetary Waves and Eddies:
A Privileged View from Satellite Altimetry
Paolo Cipollini, Anna C. S. Sutcliffe, and Ian S. Robinson
12.1 Introduction
Satellite altimetry allows sustained observations of a wide range of ocean dynamics, from features spanning just a few tens of km to the mean global sea level
spatially, and from a few days to decades temporally, with profound repercussions on our knowledge of the oceans and how they affect climate. Amongst the
many success stories for altimetry, one particularly dear to ocean dynamicists is the
systematic detection, characterization and tracking of large- and meso-scale propagating features, virtually ubiquitous in the world’s oceans, and their classification
as either planetary waves or eddies, which has involved significant efforts by several research groups. In this chapter we review (in Section 12.3) the main results of
these efforts, and highlight the important implications that those findings have had
on our understanding of how the ocean works. We also discuss (in Section 12.4)
several intriguing questions that have been prompted by the satellite-based observations of propagating features – sometimes challenging the previous knowledge
based on insufficient experimental data, other times opening completely new paths
of investigation into scientifically uncharted waters. But first we start (in Section
12.2) with a brief explanation of the importance of propagating systems for oceans
and climate.
12.2 The Importance of Oceanic Propagating Features
Oceans play a crucial role in the Earth’s climate system and in mediating its response
to the present radiative forcing imbalance, especially at the longer time scales.
Ocean dynamics can be divided into a variety of components, each of which can
be considered individually at its own scale, but it is important to keep in mind that
it is the interactions between all the components at different scales that makes the
P. Cipollini (B)
Ocean Observing and Climate Research Group, National Oceanography Centre,
Southampton SO14 3ZH, UK
e-mail: cipo@noc.soton.ac.uk
195
V. Barale et al. (eds.), Oceanography from Space,
DOI 10.1007/978-90-481-8681-5_12, C
Springer Science+Business Media B.V. 2010