Fortunately, Jeff Miller, skipper of the Bombora, volunteered for the rescue mission. Both heating events occurred under the influence of a blocking high in the Tasman but the location of the high and the nature of the disruptions to the high created quite different conditions off the west coast of New Zealand (Figure 1). With the help of well-tuned and validated algorithms, the values of remote sensing reflectance from Ocean Colour satellites can be used to estimate Chlorophyll-a concentration and other marine particles and substances afloat. Original Forecast: With moderate to strong southerly winds forecast by the Bureau of Meteorology and waves of 1.5-2m from the southwest, this years Port to Pub swim will be more challenging than the Rottnest Island swim last month. Observations of water temperature from the AIMS Davies Reef station, 18.8S 147.6E (Figure 1), show temperatures have dropped by well over 1C since Friday. For some time now, we have made it easy for you to see how anomalous SST values are, by showing the anomalies in centile form. The optimiser helps you decide how much of an adjustment you need. Sea level anomalies, SLA (white contours), indicate a 30cm depression which appears to be off-centre from the SST anomaly. A recently developed temperature climatology (GBR1-SSTAARS) for the GBR which combines five years of eReefs GBR1 model output with the SSTAARS climatology (based on 25 years of SST, 1992-2016) helps to assess the sub-surface glider observations. Along with the cold water, upwelling brings nutrients up to the surface where the phytoplankton can use it and grow. This year, although the central Tasman peaked at 2-3C above average, coastal temperatures were cooler than average (by up to 3C) and have remained cool for much of February. Well, now you can. This summers monthly mean temperatures for the northern, central and southern GBR (Fig. Bluebottles can be found in large armadas floating around the Pacific Ocean and with their buoyant sail float high in the water and go wherever the wind takes them. All three ocean observing systems reveal the main flow of the East Australian Current separating from the shelf and heading off towards New Zealand. What we aim to achieve with Argo floats with a lot of planning and effort, elephant seals seem to achieve effortlessly. The Nio indices can give us some indication of what is to come for the summer of 2017 but leading CSIRO scientist, Ming Feng, warns that the contribution of local air-sea coupling remains unpredictable. The optimiser gives you the hourly forecast currents (from the Oceans Institute of the University of Western Australia) for the next Saturday. There was an intense burst of heat in early January, particularly in the central region, but heavy cloud in the later part of January and for much of February kept the monthly anomalies relatively low. But disappointingly, from a morning dip perspective, the news is not good: the water is presently 19.5C, about 2less than climatology, sitting somewhere in the lowest decile, i.e. As has been widely reported (but usually for averages over much larger regions), almost all of the time series of temperature anomalies indicate a clear warming trend, including over the Great Barrier Reef. This tracking is possible due to their signature in Sea Level Anomaly (SLA) fields. Winter cooling is usually greatest in shallow coastal waters because the convective cooling spreads the heat loss throughout the water column, so the same heat loss will result in colder temperatures in shallower water. Physalita washed up on the beach in Worimi National Park, where she was picked up by NPWS rangers, while the 3rd float, Tito, made its way into a narrow gully in the rocks north of Wollongong. Shown at right is the diatom Ditylum brightwellii. Our new 6-day composites for regions of the South Pacific allow us to monitor the location of the floats andthe oceanproperties and circulation of this area. Fisheries Oceanography. I don't recall ever seeing this before (so good thing the outage was not irrecoverable). Lett. The time series provide a way of putting events in the context of the last three decades. Conversely the low sea levels associated with a cold core eddy will drive a northward shelf current. The February 2019 deployment demonstrates the interplay between coastal dynamics and the offshore influence of the East Australia Current (EAC). The development of a warm mixed-layer throughout the month can be seen in the Argo temperature profiles. What will happen next? Thetrue colourimagery in Figure 1 is a goodexample of how different particulate suspended matter can be seen from space. Many people know that the sea level goes up when the atmospheric pressure goes down. When the February glider (Figure 1, movie) was deployed off St Helens, in the northeast of Tasmania, the first transect indicated relatively cool temperatures consistent with the northward coastal current and the localised upwelling seen in the Four-hour SST on that day and the 13C water the glider sampled at the bottom on the outer shelf. That is not much most of the time but in the centre of a 960hPa low pressure system it amounts to a rise of 50cm. Bernadette Sloyan and her team are retrieving and replacing the mooring array and on board, Iain Suthers and a team of biologists are collectingsamples of larval fish and the fine zooplanktonic food. What is unusual about this event, however, is not so much the cold but how long it has lasted and how much of the coastline it affected. On 23 January, locals reported extraordinary water temps at Bar Beach Narooma of up to 24 degrees this week to the ABC. The EAC array was designed to capture the entire breadth and depth of the flow. Heating was the most persistent in the south with many places on and off the shelf experiencing 15-30 days of extreme temperatures. Sub-surface sections through the fading eddy showed lenses of subducted water (positive temperature, salinity, and oxygen anomalies) trapped around 300 m depth (Figure 2). Jason-2 begins a new phase: The king is dead, long live the king! In the mean time, see our constantly-updated maps of ocean data Tracking theocean temperature and salinityand the pathway of the floats to Australias east coast will provide insights into thecirculation of the western Pacific Ocean. al. Noticed something interesting, on this website, or on the water? On the Leeuwin Current System and Its Linkage to Zonal Flows - AMETSOC Where's Mark? our maps of 6-day-average anomalies), because a cyclone needs a deep reservoir of heat for growth, not just a shallow one. The Leeuwin Current (LC) off Western Australia is anomalous in that it is the only poleward-flowing eastern boundary current globally. All loggers indicate that temperatures have fallen below or are close to the normal range (defined as within 2 standard deviations of the daily average). There is a two month delay between the sea level anomaly off Perth and the region north of New Guinea. Sub-surface measurements provided by this research voyage will be invaluable to understand the magnitude of the mixing, shear, and instabilities in these two case studies, as well as the impact on biological productivity. Farther south, a textbook anticyclonic eddy shed by the East Australian Current is lingering off Bass Strait. Observations from RV Solander in early February indicate that the opposite is true. However, keep in mind that closer to shore the currents can be wind-driven. the 'bigger picture', showing how the currents in the shallower waters of the continental shelf What happens to these eddies when they reach Tasmania? South Australia, on the other hand, has had strong wind-driven upwelling since mid-January. In July of both 2015 and 2016 there were large eddies off the NE of Tasmania impacting on the eastern Orange Roughy spawning ground during their spawning time. The EAC this summer has been particularly odd. Being early October, the September averages for surface temperature and sea level have just become available. The graph at right shows that the difference from usual in summer was positive, but not as great as the previous winter, when average sea surface temperature (SST) of the ocean off Eastern Tasmania remained over 1 degree above average. There, the ocean circulation is dominated by the strong, eastward flowing Antarctic Circumpolar Current. These high values may be influenced by the presence of not only phytoplankton, but also of fine suspended riverine sediments and coloured dissolved organic matter (CDOM). From the Four-Hour SST, however, it appears the cool water is being advected from the east and south, possibly as far south as the cold core eddy at 158E, 32.5S (Figure 2). CSIRO argue that the effect of winds and waves cannot be ignored, because the flaperon must have floated within the uppermost few meters of the ocean, where it would have been subject to the Stokes drift, no matter how little freeboard it had to prevent it from sinking. However, none of these passes coincided over the region of interest to be useful in this event. 2) is above 95 for a large region between 20S and 10S, indicating that the temperature anomaly extends hundreds of metres beneath the surface. All of these factors mean that the prevailing currents are usually northward, particularly after several days of The trough inhibits the usually strong southerly winds that bring cooler air from the south and which also generate upwelling that mitigates the warming. The onshore winds responsible for bringing the moist air from the Coral Sea to feed the clouds are driven by the pressure gradient between the low trough in the north (including TC Esther in the Gulf) and the high pressure system in the Tasman Sea. This dominant pattern is illustrated above right. Nevertheless, all the signs are there. It was also preceded by a series of weak low pressure cells (e.g. Further south, upwelled water has been cooling beach temperatures along the northern and central NSW coast and in the Tasman Sea the water is warming. In fact this year, more of the ocean has broken records than any other year since 1981. However, boats approaching Tasman from a wide angle may gain an extra 1 knot of favourable current on the northwestern edge of this feature. Mid-February is the time when water temperatures are usually at their maximum so this is the danger period for coral bleaching. The maps also include the mean wave periods and peak wave direction of the longer swell waves from Sentinel-1 SAR passes (black, white, and grey circles). Without detrending, it is even higher. This speculation rests on modelling that suggested that the flaperon found on La Reunion on 29 July 2015 probably entered the ocean more than 1000km north of the present sea floor search area. However, when winds have been weak, as they have off Perth for a few days, the satellite SST may only represent a shallow surface layer. Cloud is, of course, the bane of observers of satellite SST and Himawari-8 cannot see through cloud, but with so many looks there is a much better chance to piece together a clear view. This cooling represents a significant relief from the previous 10 days of heatwave conditions and appears to be widespread with similar cooling at Heron island (23.5S) and Yongala (19S).