Archive for the ‘Ecology’ Category

Kirby Cove, three weeks after Cosco Busan oil spill

Tuesday, December 4th, 2007

We visited Kirby Cove on 23 November, three weeks after the Cosco Busan struck the Bay Bridge on 7 November. There was some oil on the west end of the beach, but otherwise it looked clean. Some of the shallower tidepool areas looked scoured of life, but I’m not certain of that without checking earlier photos. Deeper tidepool areas (we were there right at an exceptionally low -1.7 meter tide) still had plenty of anemones, feather boa kelp, and other organisms. The spill happened at neap tide, so the lowest tidal areas probably escaped exposure to the oil.

Kirby Cove lies west of the Golden Gate bridge on the north (Marin) side of the strait. One can see downtown San Francisco, the San Francisco Bay, the entire length of the northern, strait facing shore of San Francisco, and the Pacific ocean from it. It is part of the Golden Gate National Recreation Area, and as such is managed by the National Park Service.

Clicking on one of the images below takes you away from this blog to images for that day.

Rodeo Beach oil spill cleanup

Saturday, November 10th, 2007

Visible on Rodeo beach in the photos below are a dozen or so hazardous materials suit clad workers (see enlargement, below), who are nearly indistinguishable from the tens of white bags of oiled beach material that line the north end of the beach’s high tide line.

On November 7th, a container ship, the Cosco Busan, struck a glancing blow to one of the San Francisco Bay Bridge’s support fenders. The bridge was unaffected, but the Cosco Busan suffered a 40 meter gash 4 meters above the water line, which ruptured fuel tanks containing viscous bunker oil. Within an hour or so 220,000 liters had spilled into the bay, and within a day or two the oil had reached as far north as Bolinas lagoon (the mouth of which lies just below the northern most ridge visible in the bottom photo), and as far south as Hayward, a distance spanning 80 kilometers.

Kirby Cove, photographed the week before and published in this blog’s previous entry, was heavily oiled, and presumably tidal zone organisms were affected. The bottom photo was taken from a point just north of the lighthouse at Point Bonita (the light house is located on the Golden Gate’s northern, ocean side), and Kirby Cove is about 3 kilometers closer to San Francisco Bay on the same side of the Gate.

All of the coast visible in the picture below was affected by the oil spill, but the only 5% (or less) was actively being cleaned up, as is visible by looking at the coast in the other photos from this set.

Clicking the photo below will take you to the contact sheet for that day (and away from this web log).


Photographs of earth in context

Friday, September 7th, 2007

The wikipedia entries earthrise, the blue marble, and pale blue dot are pretty good at giving the significance of photos of earth from various NASA missions.

The photographs provided humanity with an epiphany equivalent to revelations such as Darwin’s theory of evolution, the Alvarez team’s discovery of an iridium layer at the K/T boundary (and comet Shoemaker-Levy’s subsequent impact on Jupiter), and Hutton’s observation of deep time, as revealed in the Jedburgh unconformity.

For the first time, we had not merely an abstract understanding of the scale of our planet; rather, we also had photographs that showed the planet in the context of its local environment.

Denial is a Tributary of the Eel River

Friday, August 4th, 2006

I’ve just returned from three days in Humboldt Redwoods State Park (located in Humboldt County, California). Among the publications we picked up in the visitor center was a 32 page booklet entitled “The Killer Eel: A Pictorial Story of the Havoc Caused by the Christmas, 1964 Flood Disaster.” I’m not quite sure of the provenance of the publication, given that no date of publication was listed, but the last page did state that “The Humboldt Beacon” were the

“publishers of this booklet,” and, that “Our publisher is J. Dwight O’Dell, Fortuna.”

The booklet, although an excellent compilation of photos of the 1964 flood, made the rather astonishing assertion that the rapacious logging practices of the previous century had no relation to the flood. What’s more, the opening article of the booklet, titled “Where does a flood come from to become a record flood of disaster proportions?” (sic) seemed to cast aspersions on the motives and integrity of those who asserted such. To wit, the article opened by stating: “It might seem silly, but a good many people are trying to use both the 1955 and 1964 floods as reasons or guideposts for their own brand of thinking, how to blame the flood on something else than water.” The article also states: “Perhaps there were contributing factors, but rainfall, lots of it, and more and more of the same, were the main factors of the storm, abetted by the melting snows.”

On the next page — it’s not quite clear if this is a continuation of the article on the first page, given that the font changes, and that there is a boxed, bolded title (”They had a Flood in 1862, Which Many Believe to Have Been Actual Record; No Lumber Men to Blame Then” (sic)) — the motives of those who claim that poor land management greatly worsens the effects of floods are called into question again. The opening paragraph of this page states:

The much maligned lumbermen of the redwood region are finally finding themselves on the side of the Angels. But “those up there” are hard to attack so the forester is taking the blame for “excessive” damage caused by the current flood.

A few paragraphs on the article states:

But it is interesting … to note that there were other similarities between the current water rampage and the flood of 1862. Then, as now, not all people looked for someone to blame for a natural disaster — many went to work.

The article’s somewhat dour view of the character of those who question the region’s recent forestry practices’ long term viability would be an almost comical ad hominem attack were it not in a publication being sold in a California State Park visitor center. Attacks of this sort are, at the least, a classically demogogic diversion from the question of whethor, in fact, the rapacious devouring of this region’s resources, as executed of late by corporations such as Louisiana Pacific and Pacific Lumber / Maxxam, are either sustainable in the long term, or, given the poverty that appears to have resulted from the collapse of the northwestern timber industry, are in the interests of the community as a whole.

In the most severe analysis, this kind of misinformation, coupled with the tendency of the exhibits at state parks visitor centers in Needle Rock (Sinkyone Wilderness State Park) and Humboldt Redwoods State Park to gloss over the genocidal nature of Euro-American contact with indigenous inhabitants, amounts to a kind of collective amnesia; a denial, if you will, of the darker aspects of the area’s history. It is as if a museum at Auschwitz made mention of the curious folkways of the Jews, but failed to note the untidy events of not long ago. That this kind of mentality persists does not bode well for the changes in policy needed if areas such as Mendocino and Humboldt are to recover from the collapse of their once abundant, resource based economies.

The Humboldt Beacon in its contemporary form appears to continue to blame bearers of the message that mismanagement of local resources is unwise, rather than blame the mismanagers themselves. The excerpt below is from an undated article posted on its website (downloaded 4 August 2006) titled Judge to hear Eel River Sawmills settlement next month (byline: G.C. Duerden). Note that the article quotes the words ‘threatened species’, in reference to the Northern Spotted Owl’s listing by the US Environmental Protection Agency, as if the article’s author somehow didn’t believe that the owl is indeed threatened with extinction. Note also that, according to the article, “Lawsuits” cut back timber harvests rather than federal concern regarding species viability (dependent as they are on the 3% of old growth redwoods as yet unharvested), nor an unsustainably large timber harvest over the past century.

Eel River Sawmills, which was formed in 1958, has had a bumpy history. The 1964 flood destroyed the mill — the stock of cut timber and the entire log dock were washed away — and put owner Mel McLean into heavy debt as he literally encumbered everything he owned to rebuild the company. By 1973 the company had fully recovered.

Times were good through the 1980s, and the employee ranks swelled to 450 or so. The Northern Spotted Owl came to prominence as a �threatened species� under the 1990 Endangered Species Act, and that was the start of the spotted owl effect. The volume of timber from the forests was cut to one-third the volume of previous years.

Lawsuits cut timber sales back farther, in 1992, to about 11 million board feet. In 1993 sales dropped again to just over 5 million board feet. By 1996 it was back up to 10 million board feet. In 1999 it jumped close to 30 million board feet being sold annually.

Apparently, all evidence to the contrary, attitudes towards resource management haven’t much changed, despite that precious little “resource” remains to be managed.


Related Articles

Cumulative Watershed Effects: Caspar Creek and Beyond, Leslie M. Reid, Research Geologist, USDA Forest Service Pacific Southwest Research Station, Redwood Sciences Laboratory, 1700 Bayview Dr., Arcata, CA 9552. An abbreviated version of this paper was presented at the Conference on Coastal Watersheds: The Caspar Creek Story, May 6, 1998, Ukiah, California. Excerpt:

A standardized impact evaluation procedure could not be developed because of the wide variety of issues that might need to be assessed, so analysis methods were left to the professional judgment of those preparing timber harvest plans. Unfortunately, oversight turned out to be a problem. Plans were approved even though they included cumulative impact analyses that were clearly in error. In one case, for example, the report stated that the planned logging would indeed introduce sediment to streams, but that downstream riparian vegetation would filter out all the sediment before it did any damage. Were this actually true, virtually no stream would carry suspended sediment. In any case, even though timber harvest plans prepared for private lands in California since 1985 contain statements attesting that the plans will not result in increased levels of significant cumulative impacts, obvious cumulative impacts have accrued from carrying out those plans. Bear Creek in northwest California, for example, sustained 2 to 3 meters of aggradation after the 1996-1997 storms, and 85 percent of the sediment originated from the 37 percent of the watershed area that had been logged on privately owned land during the previous 15 years (Pacific Watershed Associates 1998).

EPA’s recent listing of 20 north coast rivers as “impaired waterways” because of excessive sediment loads, altered temperature regimes, or other pervasive impacts suggests that whatever the methods used to prevent and reverse cumulative impacts on public and private lands in northwest California, they have not been successful. At this point, then, we have a better understanding of what cumulative impacts are and how they are expressed, but we as yet have no workable approach for avoiding or managing them.

A Fallen Giant: Remembering Tim McKay, The North Coast Journal, 3 August 2006.

The California Wild Heritage Act is a California Wilderness Coalition campaign in favor of pending Federal legislation to extend Wilderness Act protection to a additional lands.

High Waters! The floods of 1955 and 1964 and The Bull Creek Watershed reshaped by timber tax
Friends of the Eel River page describing impacts of post-WWII logging boom on sediment load, habitats, species diversity, and stream capacity. From the same page, this pair of aerial photos from October 1947 and August 1954 shows the extent of the deforestation, and indicates the state of the watersheds just before the catastrophic floods of 1955 and 1964.

Pacific coast plankton die-off

Tuesday, July 12th, 2005

As reported in the San Francisco Chronicle, a die-off of plankton has occurred in the waters off of Washington, Oregon, and California due to a cessation of upwelling of cold waters. From the Chronicle article:

“Things are pretty grim up here,” said Bill Peterson, an oceanographer with the National Marine Fisheries Service office in Newport, Ore.

Peterson said a major die-off of double-crested cormorants recently occurred in Oregon, and juvenile salmon numbers have dropped precipitously. Both events, he said, are likely due to the warm water.

“We do salmon surveys every spring and summer,” he said. “Normally, we catch several hundred salmon in the spring. This year we caught eight. And we usually get several thousand fish in the summer. This year, it was 80.”

Peterson said the water temperature off Oregon in late June is normally 10 degrees Celsius (about 50 Fahrenheit), “and this year it’s 16 degrees (about 61 F). Our (upper layer of warm water) is normally 15 meters thick, and this year it’s 30 meters. Krill numbers are down, and the plankton we are seeing are as unusual as can be — warm water species that you’d find off San Diego or Monterey.”

Peterson said it is unlikely Oregon waters will cool significantly this summer.

“It takes an enormous amount of (offshore wind) energy to push that much warm water offshore, which is what we would need to see for significant upwelling,” he said. “I don’t see that happening anytime soon.”

Bolling Allerod Antarctic Meltwater Pulse as Trigger for Younger Dryas

Wednesday, March 2nd, 2005

Wandering about more in a completely casual, amateurish way, I found a rather interesting citation. It says, in short, that an Antarctic meltwater pulse at the end of the last ice age strengthened North Atlantic Deep Water (NADW) formation, thereby warming the North Atlantic, which caused a pulse of meltwater from the Laurentide and Fennoscandian ice sheets, which then shut down the NADW, thus causing the Younger Dryas. Got that?

The Younger Dryas is an anomalous 1300 year cold snap just after the end of the last ice age. It seems to have begun and ended with astonishing rapidity, and involved a 7 degree C temperature drop globally in as little as 20 years. Essentially, the world emerged from the last ice age briefly, and then snapped back into and out of it.

Oh, the Bolling-Allerod of this entry’s title is the interstadial (that is, warm period) that ended the last ice age.

Here’s the cite (It’s from PubMed, here):

1: Science. 2003 Mar 14;299(5613):1709-13. Related Articles, Links

Comment in:

* Science. 2003 Mar 14;299(5613):1645.

Click here to read
Meltwater pulse 1A from Antarctica as a trigger of the Bolling-Allerod warm interval.

Weaver AJ, Saenko OA, Clark PU, Mitrovica JX.

School of Earth and Ocean Sciences, University of Victoria, Post Office Box 3055, Victoria, British Columbia V8W 3P6, Canada. weaver@uvic.ca

Meltwater pulse 1A (mwp-1A) was a prominent feature of the last deglaciation, which led to a sea-level rise of approximately 20 meters in less than 500 years. Concurrent with mwp-1A was the onset of the Bolling-Allerod interstadial event (14,600 years before the present), which marked the termination of the last glacial period. Previous studies have been unable to reconcile a warm Northern Hemisphere with mwp-1A originating from the Laurentide or Fennoscandian ice sheets. With the use of a climate model of intermediate complexity, we demonstrate that with mwp-1A originating from the Antarctic Ice Sheet, consistent with recent sea-level fingerprinting inferences, the strength of North Atlantic Deep Water (NADW) formation increases, thereby warming the North Atlantic region and providing an explanation for the onset of the Bolling-Allerod warm interval. The established mode of active NADW formation is then able to respond to subsequent freshwater forcing from the Laurentide and Fennoscandian ice sheets, setting the stage for the Younger Dryas cold period.

PMID: 12637739 [PubMed]

Disaster, the Cottage Industry

Tuesday, March 1st, 2005

Ah, disaster: it’s so much fun. I’ve long had an interest in geology, and that led in turn to related areas, such as glaciology, paleoclimatology, and the like.

The Vredefort dome
Vredefort dome, South Africa
Space shuttle image STS51I-33-56AA

I just watched the movie, The Day After Tomorrow, and following that I was browsing the net, checking out what has been found in the attempt to piece together the transition from the last ice age to this most recent of interregnums, our warm period, the Holocene. And of course one finds on the net plenty of scientific information, but also a plethora of wacky obssession with doomsday scenarios. It’s a curious propensity, this fascination with events approaching from the periphery of human consciousness and memory. Shadows from beneath the bed.

The biggest local cosmic train wreck so far? The Vredefort dome.

Where else would one find descriptions as colorful as this (from the link above):

This ring of hills comprises quartz conglomerates as found in the gold-bearing strata of the Witwatersrand reefs.

Vredefort Dome, Village1s
Village, Vredefort dome, South Africa
Vredefort Dome, Village stones 1s
Village stones, Vredefort dome, South Africa

The white quartz pebbles are evident. This was once the bed of a fast flowing water course which
deposited grains of quartz and the pebbles. This area was mined for gold in the 1880’s. However the concentration of gold was much poorer than at Johannesburg, and the diggings were soon abandoned. Old mine adits are still to be seen in the hills. This is the Amazon Reef.

The outermost ring of hills was home to a quite different group of people in the 1500’s to 1700’s. These were SeSotho/SeTswana-speaking farmers. This village at Askoppies was a defensive position on the crest of the hill, but it did not save the village from destruction, by the warriors of Mzilikazi. The view shown above left looks east, back in towards the inner rings of the Vredefort dome.

The stone walls of the village are shown above right. They are made of the fine-grained grey Ventersdorp lavas that comprise this ridge. These rocks are 2700 million years old.

of illustrative climate-change related charts is here (I’ll try to include attributions later, but most are from the excellent American Scientist article cited in the graph caption, below).

My favorite of these? The chart that shows anthropogenic induced change in the atmospheric concentration of C02. The two graphs shown are derived from an ice core from Vostok, Antarctica. The top chart is of deuterium, a proxy for temperature. The bottom is of CO2, parts per million. The time scale at the bottom is in thousands of years before the present.

Vostok ice core

Vostok Ice Core, Antarctica, 0 to 160,000 years before present
Top chart is deuterium (per mil).
Bottom chart is C02 (parts per million by volume).

Graphic from “Rapid Climate Change,” Kendrick Taylor,
American Scientist, July-August, 1999.

The Holocene is the 10,000 or so year-long warm period that we’re living in now. The cold stretch of 125,000 years prior to the Holocene is the most recent Pleistocene era glaciation, know as the Wisconsin ice age in North America. Just before the Wisconsinin is the Eemian, another brief warm spell like our own; and before that lies an earlier glacial period (but still lying within the 2 million year extent of the Pleistocene). The red spike on the left side, bottom chart is the increase in atmospheric C02 caused by humans in the industrial era, now 150 years old.

The Younger Dryas

Monday, February 28th, 2005

I’ve been reading a little more about the Younger Dryas, which was an abrupt state change in climate, probably global in scale, from warm back to cold, lasting for about 1300 years, and ending 11640 years before present. This AGU page describes the event:

The Younger Dryas (YD) was the most significant rapid climate change event that occurred during the last deglaciation of the North Atlantic region. Previous ice core studies have focused on the abrupt termination of this event [ Dansgaard et al., 1989] because this transition marks the end of the last major climate reorganization during the deglaciation. Most recently the YD has been redated–using precision, subannually resolved, multivariate measurements from the GISP2 core–as an event of 1300 +/- 70 years duration that terminated abruptly, as evidenced by an 7C rise in temperature and a twofold increase in accumulation rate, at 11.64 kyr BP [ Alley et al., 1993] (Figure 2). The transition into the Preboreal (PB), the PB/YD transition, and the YD/Holocene transition were all remarkably fast, each occurring over a period of a decade or so [ Alley et al., 1993]. Fluctuations in the electrical conductivity of GISP2 ice on the scale of <5-20 years have been used to reveal rapid changes in the dust content of the atmosphere during the same periods and throughout the last glacial [ Taylor et al., 1993b]. These rapid changes appear to reflect a type of “flickering” between preferred states of the atmosphere [ Taylor et al., 1993b], which provides a new view of climate change. Holocene climates are by comparison stable and warm.


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