National Science and Implementation Plan 2015-25 IMOS is a national collaborative research infrastructure, supported by Australian Government. It is led by University of Tasmania in partnership with the Australian marine & climate science community. 0 Table of Contents Table of Contents .................................................................................................................................... 1 1 Executive Summary ......................................................................................................................... 5 2 Outline............................................................................................................................................. 6 3 Introduction .................................................................................................................................... 7 4 The Australian Context.................................................................................................................... 9 4.1 The need for ocean observing in Australia ............................................................................. 9 4.2 Australian ocean observing in a global context .................................................................... 13 4.3 Research and operational observing systems in Australia ................................................... 14 4.4 Structure of the Australian marine and climate science community ................................... 16 4.5 The position of IMOS in marine and climate science............................................................ 18 5 The role of Node science plans in guiding IMOS investment ....................................................... 23 6 The IMOS Science Nodes .............................................................................................................. 26 6.1 Bluewater and Climate Node ................................................................................................ 27 6.2 Regional Nodes ..................................................................................................................... 28 6.2.1 Regional features .......................................................................................................... 28 6.2.2 Coastal States and Territories ....................................................................................... 29 6.2.3 Science capability .......................................................................................................... 29 6.2.4 IMOS regional coastal Nodes ........................................................................................ 29 6.3 Node governance .................................................................................................................. 31 6.4 Major research themes that integrate across Nodes ........................................................... 32 6.5 Collaboration with other nationally significant programs .................................................... 34 7 Scientific Background, by Major Research Theme ........................................................................ 38 7.1 Multi-decadal ocean change ................................................................................................. 38 7.1.1 The global energy balance (temperature) and sea level budget .................................. 38 7.1.2 The global ocean circulation ......................................................................................... 40 7.1.3 The global hydrological cycle (salinity) ......................................................................... 42 7.1.4 The global carbon cycle (Inventory, air sea fluxes, physical controls) .......................... 43 7.1.5 Spatial and temporal scales .......................................................................................... 44 7.1.6 Modelling Activities ....................................................................................................... 44 7.1.7 Science Questions ......................................................................................................... 44 7.1.8 Variables required to address science questions ......................................................... 45 1 7.1.9 Platforms required to deliver observations .................................................................. 46 7.2 Climate variability and weather extremes ............................................................................ 48 7.2.1 Interannual Climate Variability ..................................................................................... 49 7.2.2 Intra-seasonal variability and severe weather .............................................................. 53 7.2.3 Modes of variability in a changing climate ................................................................... 56 7.2.4 Spatial and temporal scales .......................................................................................... 56 7.2.5 Modelling activities ....................................................................................................... 57 7.2.6 Science Questions ......................................................................................................... 58 7.2.7 Variables required to address science questions ......................................................... 59 7.2.8 Platforms required to deliver observations .................................................................. 59 7.3 Major boundary currents and inter-basin flows ................................................................... 61 7.3.1 East Australian Current (EAC) system (including Tasman Outflow, Flinders Current and Gulf of Papua Currents) ................................................................................................................ 62 7.3.2 The Leeuwin Current (LC) system (including the Zeehan Current) ............................... 64 7.3.3 The Indonesian Throughflow (ITF) ................................................................................ 66 7.3.4 Antarctic Circumpolar Current and Antarctic Circumpolar Wave ................................ 67 7.3.5 Eddy Processes in boundary currents. .......................................................................... 68 7.3.6 Spatial and temporal scales .......................................................................................... 69 7.3.7 Modelling activities ....................................................................................................... 70 7.3.8 Science questions .......................................................................................................... 71 7.3.9 Variables required to address science questions ......................................................... 71 7.3.10 Platforms required to deliver observations .................................................................. 72 7.4 Continental Shelf and Coastal Processes .............................................................................. 73 7.4.1 Boundary current eddy –shelf interactions .................................................................. 74 7.4.2 Upwelling and downwelling .......................................................................................... 76 7.4.3 Shelf Currents ................................................................................................................ 79 7.4.4 Wave climate, including internal and coastally trapped waves.................................... 81 7.4.5 Spatial and temporal scales .......................................................................................... 83 7.4.6 Modelling activities ....................................................................................................... 83 7.4.7 Science questions .......................................................................................................... 85 7.4.8 Variables required to address science questions ......................................................... 85 7.4.9 Platforms required to deliver observations .................................................................. 86 7.5 Ecosystem Responses ........................................................................................................... 88 7.5.1 Ocean Chemistry – Nutrients ........................................................................................ 90 2 7.5.2 Ocean Chemistry – Carbon and acidification ................................................................ 91 7.5.3 Microbial community .................................................................................................... 92 7.5.4 Pelagic: Plankton ........................................................................................................... 93 7.5.5 Pelagic: Nekton ............................................................................................................. 95 7.5.6 . Benthos ....................................................................................................................... 99 7.5.7 Modelling activities ..................................................................................................... 103 7.5.8 Spatial and temporal scales ........................................................................................ 105 7.5.9 Science questions ........................................................................................................ 106 7.5.10 Variables required to address science questions ....................................................... 107