Tag Archives: Monkey Beach reef

More Ocean Temperature Data & More Diving, This Weekend – Great Keppel Island

From Jennifer Marohasy

By jennifer

I’m back in Yeppoon.  This afternoon I was at Wreck Point, and in the distance, over my left shoulder, you can see Great Keppel Island.  According to the New York Times there is mass coral bleaching there (CLICK HERE).  A photograph of the corals at Monkey Beach reef featured in an article in that newspaper just yesterday.   It was apparently taken on March 5, 2024.

(I’m hoping to see these corals for myself this weekend.   To be sure to know what I find out, to be sure to see the photographs I’m hoping to take, consider subscribing for my free email updates (CLICK HERE).)

The New York Times attributes the bleaching to extraordinarily warm ocean temperatures.  Of course, there is no chart, no data – no information on actual ocean temperatures.

It is exceedingly rare for any newspaper to ever publish location specific temperature data.  In fact, that is the only real type of temperature data: location specific data.    Everything else is a construct – a contrived statistic.

The picture of the bleached corals at Great Keppel Island, published in the New York Times, was apparently provided by AIMS (Australian Institute of Marine Sciences).  Of course, they also have temperature data.  One of their key weather stations is at Square Rocks just to the northwest of Great Keppel Island.  There is data for the period December 19, 2009, through to February 19, 2024.  This data, consistent with the information I have previously published for the central region does not suggest that ocean temperatures have been particularly warm this last summer.

AIMS water temperature data for Square Rock just to the northwest of Great Keppel Island measured at 2.9 and 7.9 metres depths.

(There is very little difference in the two temperature profiles at the different depths so there is much overlap in the above chart.  For clarity I will also now post these times series separately.

There is sea level data for Rosslyn Bay, just across a little further to the east from Great Keppel Island.  (I will be catching the ferry to Great Keppel Island from Rosslyn Bay marina at the end of the week, weather permitting and passing Square Rock.)

This sea level data indicates monthly averages are towards the low end of their annual cycle, and have stalled.   This is consistent with an El Nino event and the water sloshing over to the other side of the Pacific Ocean, you can read more about the phenomenon at the NOAA website (CLICK HERE).

Monthly sea levels at Rosslyn Bay Marina, more information https://psmsl.org/data/obtaining/stations/1760.php

Could it be that the bleaching at Great Keppel Island has more to do with lower-than-average sea levels for this time of year, rather than unusually warm water?  I’m just asking the question.  (It is perhaps better to have questions that cannot be answered, rather than answers that cannot be questioned.)

Square Rock also has air temperature data, and, of course, the two move somewhat in unison except that the air is consistently a little cooler.   This is the air that has all the greenhouse gases, that is meant to be warming the ocean.

AIMS air temperature and water temperature data for Square Rock, just to the northwest of Great Keppel Island.

Of course, only someone who believes the nonsense from the experts and who can’t read a chart could believe that the air warms the ocean!

The sun warms the ocean that warms the atmosphere.  That is what happens in the tropics at least, which is where I live.

It has been a very wet summer and so my much neglected garden is doing well.   It can get very dry here.  Usually drier summers are hotter summers.

MORE INFORMATION. UPDATE 17TH APRIL 2024

I’ve looked around for more information, and found water temperature data for Rosslyn Bay, that is just across from Great Keppel Island. This time series that is collected by the Australian Baseline Sea Level Monitoring Project is twice as long, beginning in 1991, and complete for this last summer.

Consistent with the AIMS data for Square Rocks, it does NOT suggest that this last summer has been particularly warm. It shows a distinct seasonal trend; it does not show global warming.

Water temperature data for Rosslyn Bay can be downloaded at http://www.bom.gov.au/oceanography/projects/abslmp/data/monthly.shtml

Fancy Fins Didn’t Help with the Visibility

According to the mainstream media it’s the southern Great Barrier Reef that has been hit hardest with coral bleaching, and particularly the corals in the Capricorn region that includes Great Keppel Island.   I have a home in Yeppoon, which is just a short ferry ride away. I have been keen to go see for myself, but the weather has been less than ideal.

Looking down at the ferry anchored in Fisherman’s Beach bay, Great Keppel Island. The water is looking rather grey-blue, because the sun is behind a cloud. (Photograph taken by Jennifer Marohasy, 15th March 2024.)

The dive shop on the island has been telling me there is some bleaching, but it’s hard to see because visibility is a problem.  That has been the situation for the last week – since John Abbot and I drove back to Yeppoon from Noosa.

By ‘visibility’ they mean the distance one can see under-the-water.

Yesterday, Friday, I nevertheless caught the ferry across to the island and made my way around to Monkey Beach reef.

Great Keppel Island is located just to the northeast of the mouth of the Fitzroy River, so when there is a lot of wind and particularly a lot of rain, the water can become murky to the extent you cannot see the corals even if they are just, one metres below, which was the situation yesterday.

Just got out of the water at Monkey Beach, the reef is a good distance out, and visibility was so bad I couldn’t see the corals.  The water nevertheless looked very blue from the beach when the sun was out.  (Photograph taken yesterday, 15th March 2024.)
The view from Wreck Point, Yeppoon, looking across Keppel Bay to Rossyln Bay marina and beyond to Great Keppel Island far in the distance on the horizon. The water at the moment is so muddy in the bay.  At other times of the year and depending on wind direction this bay can be so blue. (Photograph by Jennifer Marohasy, 16th March 2024.)

While the coral bleaching has been blamed on elevated sea temperatures, which may be the situation, it’s hard to know for sure.

The coral bleaching could be from freshwater runoff, from the Fitzroy River.

The Fitzroy River drains the single largest area (approximately 143,000 km2) of the Great Barrier Reef catchments and discharges into the largest estuary and then into Keppel Bay. The Keppel Islands within the bay have many fringing inshore coral reefs, including Monkey Bay reef.

When I look at the data for Rosslyn Bay marina, just across from the island and around the bay from where I live in Yeppoon, the most remarkable thing is the drop in sea-level at the end of last year, 2023.

Note the monthly data for Rosslyn Bay Marina, just across from Great Keppel Island.
From The Australian Bureau of Meteorology’s Australian Baseline Sea Level Monitoring Array Monthly Data Report – December 2023. The most recent report available as at March 2024.

Low tides associated with low sea levels can also cause corals to bleach; particularly if the low tides occur on sunny days when there is significant incoming solar radiation and not much wave action.

The lower than usual sea levels are perhaps due to the El Nino, with all the water sloshing across to the other side of the Pacific because the trade winds haven’t been blowing as hard as usual.

Sooner or later, I will get back out to Monkey Beach reef, and I will report what I see, once visibility has improved and I can see the corals again.  In the meantime, consider subscribing for my irregular email newsletter so that I can keep you in the loop.

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To get to Monkey Beach reef I had to walk across the island from the southern end of Fisherman’s Beach all the way to Long Beach and then cut across that headland back to Monkey Beach. The more direct route is badly eroded, and not maintained.  Photograph of Long Beach by Jennifer Marohasy, 15th March 2024.
The walking tracks on Great Keppel Island are in disrepair. This map shows theoretically how it should be, https://hikingtheworld.blog/national_park/woppa-great-keppel-island/

Can anyone find me some location specific up-to-date sea temperature data for anywhere at the Great Barrier Reef?  Not the colour maps, that are variously based on homogenised satellite records.

Acropora (branching hard corals) and painted sweetlip (fish) photographed at Monkey Beach reef on 28th December 2023, by Jennifer Marohasy when visibility was much better.
Acropora corals at Monkey Beach reef, December 2023.

*****

The feature photograph is of Jennifer Marohasy sitting in Fisherman’s Beach waiting for the ferry later in the afternoon on 15th March 2024.