Jennifer Marohasy

a forum for the discussion of issues concerning the natural environment

Archives for January 5, 2008

Exceptional rainfall produces exceptionally clean waterways

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CooperCk.jpg

I recently reported that the wet season had well and truly arrived in the Daintree, with over 700 mm of rain in five days.

More recently, Jennifer published the Australian mean rainfall total for 2007 at 497 mm, slightly more than the long-term average of 472 mm.

So, there is no question; the Daintree Cape Tribulation rainforest occupies a very wet part of Australia. Last year we recorded a total rainfall of 4,757 mm and the year before; 6,240 mm.

The most recent deluge, though, was of an intensity not seen for many years. In March of 1996, I recall that 1,219 mm fell in 48 hours. Flooding was so powerful that the Daintree River Ferry was deposited upon its pylons and the road across the heights of the Alexandra section, collapsed.

It must be said, that here in the Daintree rainforest, we brace ourselves in the face of extreme weather events, but they also remind us unequivocally of our subordinance to nature.

If I were to conservatively estimate that only one direct cyclone was to have hit every fifty years, the ancient rainforests of the Daintree would have bore the brunt of 2.7million cyclones over its 135-million year existence. On this basis, it becomes a very regular and recurring event.

In the aftermath, perhaps half the canopy is dislodged to the forest floor and as much as twice the sunlight is able to penetrate to these leafy depths of nutrient abundance. There can be no doubt that the extent of flowering and fruiting is maximised after cyclonic events. All other populations seem to multiply.

And the creeks become magnificent!

2007 Coldest this Century: Lubos Motl

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With the end of the year, and all the global warming hype, I’ve been trying to understand how hot 2007 really was globally and also the direction in which temperatures are now trending considering the satellite and near surface measurements at the NOAA and Hadley websites respectively. Of course raw numbers, graphed and ungraphed, can give a different impression depending on your starting point – be that 1979 when satellite data was first collected, 1900 when surface temperatures were already being collected, or 1998 the hottest year so far.

Nevertheless, the various data sets do suggest that globally 1998 is still far and away the hottest and that temperatures have been stable or in decline since then. Also given 1998 was so hot, and only ten years ago, and that increases and decreases in temperature tend to be incremental it is not surprising that last year can be described as the sixth or seventh warmest even if the trend is one of cooling. But is it?

Anyway, I was surprised, but also interested, to see the analysis by Lubos Motl at this blog (http://motls.blogspot.com ). He’s a physicist and has been looking at the same data sets as I have over the last few days but coming to much more interesting and definitive conclusions including that the linear trend for the satellite data for the 1998 -2007 interval is -0.48C and that December 2007 was cooler than the average December since 1979.

Read the complete blog post here: http://motls.blogspot.com/2008/01/2007-warmest-year-on-record-coldest-in.html

RSS MSU Anomalies 2005-2007.jpg
[from http://motls.blogspot.com/2008/01/2007-warmest-year-on-record-coldest-in.html showing global cooling over the short interval 2005-2007]

Sun Bears (Part 2)

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The world’s smallest species of bear, the sun bear ( Helarctos malayanus ), was classed as ‘Vulnerable’ and accepted for inclusion in the IUCN Red List in November 2007.**

The international organisation that regulates trade in endangered species, CITES, had already listed sun bear as threatened with extinction and notes that there is a trade in sun bear ‘body parts’ including for traditional medicines as discussed at a previous blog post Sun Bears (Part 1).

The sun bear lives in mainland Southeast Asia, Sumatra and Borneo and was previously listed as Data Deficient byt the IUCN, meaning that not enough was known about the species to give it a status on the Red List.

Sun bear C Gabriella Fredriksson copy .jpg
This picture of a sun bear is published with permission from Gabriella Frediksson (via Ann Novek).

Rob Steinmetz, co-chair of the IUCN Bear Specialist Group’s sun bear expert team, said in November that: “We estimate that sun bears have declined by at least 30 percent over the past 30 years (three bear generations)…
Deforestation has reduced both the area and quality of their habitat. Where habitat is now protected, commercial poaching remains a significant threat.”

[Thanks to Ann Novek for the picture and link to the IUCN media release.]

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** The IUCN Red List of Threatened Species classifies species according to their extinction risk. It is a searchable online database containing the global status and supporting information on more than 41,000 species. Its primary goal is to identify and document the species most in need of conservation attention and provide an index of the state of biodiversity. The IUCN Red List threat categories are the following, in descending order of threat:

1. Extinct or Extinct in the Wild;

2. Critically Endangered, Endangered and Vulnerable: species threatened with global extinction;

3. Near Threatened: species close to the threatened thresholds or that would be threatened without ongoing specific conservation measures;

4. Least Concern: species evaluated with a low risk of extinction;

5. Data Deficient: no evaluation because of insufficient data.