Jennifer Marohasy

a forum for the discussion of issues concerning the natural environment

Archives for August 2007

Cooling clouds – a note from Marc Morano

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An interesting new paper has been published:

Spencer, Roy W.; Braswell, William D.; Christy, John R.; Hnilo, Justin (2007)
Cloud and radiation budget changes associated with tropical intraseasonal oscillations
Geophys. Res. Lett., Vol. 34, No. 15, L15707

Abstract
We explore the daily evolution of tropical intraseasonal oscillations in satellite-observed tropospheric temperature, precipitation, radiative fluxes, and cloud properties. The warm/rainy phase of a composited average of fifteen oscillations is accompanied by a net reduction in radiative input into the ocean-atmosphere system, with longwave heating anomalies transitioning to longwave cooling during the rainy phase. The increase in longwave cooling is traced to decreasing coverage by ice clouds, potentially supporting Lindzen’s “infrared iris” hypothesis of climate stabilization. These observations should be considered in the testing of cloud parameterizations in climate models, which remain sources of substantial uncertainty in global warming prediction.

Received 15 February 2007; accepted 16 July 2007; published 9 August 2007.

The UAH press release is here.

Cirrus disappearance: Warming might thin heat-trapping clouds

The widely accepted (albeit unproven) theory that manmade global warming will accelerate itself by creating more heat-trapping clouds is challenged this month in new research from The University of Alabama in Huntsville.

Instead of creating more clouds, individual tropical warming cycles that served as proxies for global warming saw a decrease in the coverage of heat-trapping cirrus clouds, says Dr. Roy Spencer, a principal research scientist in UAHuntsville’s Earth System Science Center.

That was not what he expected to find.

“All leading climate models forecast that as the atmosphere warms there should be an increase in high altitude cirrus clouds, which would amplify any warming caused by manmade greenhouse gases,” he said. “That amplification is a positive feedback. What we found in month-to-month fluctuations of the tropical climate system was a strongly negative feedback. As the tropical atmosphere warms, cirrus clouds decrease. That allows more infrared heat to escape from the atmosphere to outer space.”

The results of this research were published today in the American Geophysical Union’s “Geophysical Research Letters” on-line edition. The paper was co-authored by UAHuntsville’s Dr. John R. Christy and Dr. W. Danny Braswell, and Dr. Justin Hnilo of Lawrence Livermore National Laboratory, Livermore, CA.

“While low clouds have a predominantly cooling effect due to their shading of sunlight, most cirrus clouds have a net warming effect on the Earth,” Spencer said. With high altitude ice clouds their infrared heat trapping exceeds their solar shading effect.

In the tropics most cirrus-type clouds flow out of the upper reaches of thunderstorm clouds. As the Earth’s surface warms – due to either manmade greenhouse gases or natural fluctuations in the climate system – more water evaporates from the surface. Since more evaporation leads to more precipitation, most climate researchers expected increased cirrus cloudiness to follow warming.

“To give an idea of how strong this enhanced cooling mechanism is, if it was operating on global warming, it would reduce estimates of future warming by over 75 percent,” Spencer said. “The big question that no one can answer right now is whether this enhanced cooling mechanism applies to global warming.”

The only way to see how these new findings impact global warming forecasts is to include them in computerized climate models.

“The role of clouds in global warming is widely agreed to be pretty uncertain,” Spencer said. “Right now, all climate models predict that clouds will amplify warming. I’m betting that if the climate models’ ‘clouds’ were made to behave the way we see these clouds behave in nature, it would substantially reduce the amount of climate change the models predict for the coming decades.”

The UAHuntsville research team used 30- to 60-day tropical temperature fluctuations – known as “intraseasonal oscillations” – as proxies for global warming.

“Fifteen years ago, when we first started monitoring global temperatures with satellites, we noticed these big temperature fluctuations in the tropics,” Spencer said. “What amounts to a decade of global warming routinely occurs in just a few weeks in the tropical atmosphere. Then, as if by flipping a switch, the rapid warming is replaced by strong cooling. It now looks like the change in cirrus cloud coverage is the major reason for this switch from warming to cooling.”

The team analyzed six years of data from four instruments aboard three NASA and NOAA satellites. The researchers tracked precipitation amounts, air and sea surface temperatures, high and low altitude cloud cover, reflected sunlight, and infrared energy escaping out to space.

When they tracked the daily evolution of a composite of fifteen of the strongest intraseasonal oscillations they found that although rainfall and air temperatures would be rising, the amount of infrared energy being trapped by the cloudy areas would start to decrease rapidly as the air warmed. This unexpected behavior was traced to the decrease in cirrus cloud cover.

The new results raise questions about some current theories regarding precipitation, clouds and the efficiency with which weather systems convert water vapor into rainfall. These are significant issues in the global warming debate.

“Global warming theory says warming will generally be accompanied by more rainfall,” Spencer said. “Everyone just assumed that more rainfall means more high altitude clouds. That would be your first guess and, since we didn’t have any data to suggest otherwise …”

There are significant gaps in the scientific understanding of precipitation systems and their interactions with the climate, he said. “At least 80 percent of the Earth’s natural greenhouse effect is due to water vapor and clouds, and those are largely under the control of precipitation systems.

“Until we understand how precipitation systems change with warming, I don’t believe we can know how much of our current warming is manmade. Without that knowledge, we can’t predict future climate change with any degree of certainty.”

Spencer and his colleagues expect these new findings to be controversial.

“I know some climate modelers will say that these results are interesting but that they probably don’t apply to long-term global warming,” he said. “But this represents a fundamental natural cooling process in the atmosphere. Let’s see if climate models can get this part right before we rely on their long term projections.”

Save the planet – drive to the shops!?

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This article is from The Times (London). Not sure what to make of this, other than perhaps a ‘green’ attack on meat eating:

Walking to the shops ‘damages planet more than going by car’

Walking does more than driving to cause global warming, a leading environmentalist has calculated.

Food production is now so energy-intensive that more carbon is emitted providing a person with enough calories to walk to the shops than a car would emit over the same distance. The climate could benefit if people avoided exercise, ate less and became couch potatoes. Provided, of course, they remembered to switch off the TV rather than leaving it on standby.

The sums were done by Chris Goodall, campaigning author of How to Live a Low-Carbon Life, based on the greenhouse gases created by intensive beef production. “Driving a typical UK car for 3 miles [4.8km] adds about 0.9 kg [2lb] of CO2 to the atmosphere,” he said, a calculation based on the Government’s official fuel emission figures. “If you walked instead, it would use about 180 calories. You’d need about 100g of beef to replace those calories, resulting in 3.6kg of emissions, or four times as much as driving.

“The troubling fact is that taking a lot of exercise and then eating a bit more food is not good for the global atmosphere. Eating less and driving to save energy would be better.”

Mr Goodall, Green Party parliamentary candidate for Oxford West & Abingdon, is the latest serious thinker to turn popular myths about the environment on their head.

Full article here.

Enjoy!

Tasmanian Pulp Mill assessment process – a note from Cinders

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Tasmanian Pulp Mill assessment process vindicated by the Federal court

The Federal court confirmed today that the Assessment of Tasmania’s proposed pulp mill was fair and reasonable and that the public had ample opportunity to state their views.
A Federal Court judge rejected the claims by the Wilderness Society and a group calling itself Investors for Tasmania’s future and dismissed their application to overturn the Commonwealth assessment process.
The Federal Court was asked to review two decisions made by the Commonwealth Minister for the Environment and Water Resources.
The first decision was to make the mill a controlled action in relation to threatened and migratory species and Commonwealth Marine Waters. The second decision was that the relevant impacts of the proposed action be assessed on preliminary documentation (eg all the documentation created under the failed RPDC process, including the Draft Integrated Impact statement, Peer reviewed reports, Supplementary information and 700 odd public submissions that had been gathered since 2004.)
The Wilderness Society made the following allegations:
• there is no valid referral of the proposal to support either decision;
• in making the first decision, the Minister misconstrued the EPBC Act, failed to take into account for the potential adverse impact of sourcing timber from Tasmanian forests to supply the pulp mill;
• in making the first decision, the Minister failed to consider whether the pulp mill would have or is likely to have a significant impact on the environment on Commonwealth land;
• the Minister misconstrued and/or misapplied the EPBC Act in making the second decision;
• in making the second decision, the Minister denied members of the public interested in the assessment procedural fairness;
• the second decision is invalid because it is affected by apprehended bias in the Minister;
• the second decision involved an improper exercise of power by the Minister; and
• the second decision was manifestly unreasonable.

The Investors appear to have also alleged that the Minister took into account Gunns’ commercial imperatives in making his decision.

The Federal Court rejected all allegations.

This means to me that the Assessment approach and decisions leading to it are valid.
The Judge was satisfied that the Minister acted in accordance with the Law, with fairness and without bias in making his decision on the assessment process that was demonstrably reasonable.

That there is no need to assess the impact of the mill on Tasmanian forests as these and the species of flora and fauna are protected by the Regional Forest Agreement.
That is was entirely appropriate for the Minister not to consider Commonwealth land. In relation to World Heritage Values the green groups did not even raise this as an issue, thus claims to UNESCO that WHA will be impacted are clearly unsubstantiated.
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Many people in Tasmania have been concerned about the process of assessment since the developer withdrew from the RPDC assessment in February, some 2 years three months after the start of the “18 month” assessment. However much of the challenges raised with the Federal Court would have applied to the RPDC process, in fact one member resigned due to a claim of bias by the Greens.

The decision now means that Tasmania can get on with the assessment process and have a decision by both the Federal Minister and the State Parliament based on the scientific evidence.

Copies of the Federal Court’s Judgment are available here.

And the winner is……1934

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Thanks to Steve McIntyre and Anthony Watts, 1998 is no longer ranked as the warmest year on record in the USA, due to the correction of a significant error. That honour now goes to 1934.

More here at ICECAP

Roger Pielke Sr also has a post about this on his climate science weblog, where Steve McIntyre has posted this comment:

“I have made my 3rd request for access to GISS source code to try to decode what they do. They have refused prior requests. Lack of access to source code makes this sort of exercise far more time consuming than it ought to be.

Yesterday they completely overwrote their US data set, changing virtually every number prior to 2000, explaining this only with a cursory comment on their webpage. In addition, they have changed their UHI adjustments so that in many cases the changed UHI adjustments offset the error in their “raw” data.

Even before these change, I was unable to track their pre-2000 data to any archive. It was sort of like USHCN adjusted data in the 1990s but diverged in earlier periods. I’ve requested a copy of the original data set or information on its provenance.

I would welcome letters to GISS urging them to fully disclose their source code.

BTW the CRU situation is much worse as they have refused to even identify the stations that they use. In fairness to GISS, they provided enough information that you could leverage on it, but CRU has resolutely refused such information. ”

Bauxite Mining in Jarrah Forests: A Note from Roger Underwood

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One of the most interesting anomalies in Australian environmentalism is that the alumina industry is destroying the jarrah forest – and nobody seems to care. At least, nobody is complaining.

Open cut mining of State Forests in Western Australia by two alumina producers (Alcoa and Worseley) has been going on for about 40 years. Mining involves clean cutting of the forest (removal of all saleable timber, including woodchips), full agricultural clearing, blasting with explosives and then removal of the forest soil. This converts the jarrah forest into a patchwork of pits 8-10 metres deep and up to 40 hectares in size. In and around the pits the remnant forest is criss-crossed with haul roads, crusher sites, conveyor belts and power lines. The rate of forest clearance is about 1000 hectares a year. It is estimated that mining will proceed for at least another 50 years.

The mined-out pits are “rehabilitated” by smoothing the edges, ripping the pit floor (a white kaolinitic clay) with bulldozers and replacing a film of topsoil. Various tree and shrub species are then sown or planted. Pre-1988 the revegetation was basically a plantation of exotic species, mostly eucalypts indigenous to NSW; post 1988 the main tree species planted or sown is jarrah.

Jarrah (Eucalyptus marginata) is a tall long-lived tree noted for its superb timber, toughness and resilience. It grows in a relatively harsh environment of long dry summers, frequent fire, and infertile soils. Jarrah occurs only in a restricted area in the southwest of Western Australia. Most of the northern jarrah forest is also an important water resource area and protects the city and goldfields water supply catchments. It also provides important habitat to native species, a range of recreational activities and is famous for its springtime display of endemic wildflowers. Jarrah timber played an important role in the development of Western Australia. It was used almost exclusively in the construction of the State’s harbours, bridges and railways, for telephone and electricity distribution, for house and building construction, for fine furniture manufacture and domestic and industrial firewood. For many decades it was the State’s third most valuable export (after wheat and wool) and was regarded as one of the world’s most beautiful, as well as strongest and most durable timbers.

In a biogeographical and ecological sense, the jarrah forest is virtually an island. It falls within the Australian south-west botanical province, known as a biodiversity hotspot – most jarrah forest can carry 60 or more different species of plants in the understorey – and is home to a unique fauna. To the west of the forest belt is the coastal sandplain, these days increasingly becoming one large residential subdivision. To the north and east are the cleared agricultural regions and to the south the narrow strip of karri forest and the Southern Ocean. The forests were traditionally managed for water production, catchment protection, sustainable timber production, wildlife conservation and recreation. In more recent times the management priority has been designated simply as “conservation of biodiversity”, but as we shall see, this is subservient to minerals production. The jarrah timber industry scarcely now exists. This has been virtually extinguished over the last 5 years as logging became a politically unacceptable activity in the state’s forests. The few small timber production operations remaining are all based on regrowth forests, where they are under constant challenge from protest groups whose aim is the total elimination of the industry.

Jarrah forest soils are lateritic and contain bauxite. This is the ore from which alumina and ultimately aluminium is produced. In the 1960s, the State government issued leases for bauxite mining over 800,000 hectares of jarrah forest, and put in place State Agreement Acts which guaranteed easy access to the leaseholders. Mining commenced in the forest in the mid-1960s and expanded rapidly. At first there was a single mine near Jarrahdale. The ore was railed to a refinery at Kwinana. Before long a new refinery had been built near Pinjarra and new mines were opened up at Del Park and Huntly on the banks of the South Dandalup dam (part of Perth’s water supply). By the early 1980s there was a third refinery at Wagerup, a new mine in State Forests south of the Murray River, another mine at Mt Saddleback and a fourth refinery near Collie. As recently as 2006 the WA Environmental Protection Authority approved a further expansion of the rate of mining for the Wagerup refinery, and there are current moves by the State government to expand the rate of mining for the Worsely refinery, so that it is likely that the annual rate of forest destruction will soon exceed 1000 ha.

There was some initial opposition to the forest mining, mainly from foresters, including a campaign run by the Institute of Foresters in the 1960s. The Institute produced an excellent booklet, detailing the undesirable impacts of mining on the forest ecosystem. However, these protests were quickly snuffed out, the problem being that most foresters at that time were also public servants, and it was illegal for them to criticise government policy, even as members of their professional institute. The “conservation movement” showed an initial flicker of interest, but this died away almost immediately. At that time and ever since, the focus of environmentalists was on the timber industry, bushfire management and forestry. Over the last 40 years, there has not been a peep of protest from any green organisation in WA (government or NGO) about bauxite mining.

In this light, it is worth looking at the mining operation in more detail. Mining eliminates the entire forest ecosystem both above and below ground. Following clearing no native plant or animal survives. Following mining the forest soil itself is irreplaceably gone. The natural landscape is greatly altered, since the best bauxite deposits are on the gravely uplands, and these disappear, leading to a landscape with less topographical variation. The post-mining revegetation is sown into well-cultivated and fertilised topsoil and comes away rapidly. Visually it resembles even-aged regeneration after clearfelling or in the gaps created by selective logging (the latter being the normal silvicultural approach in jarrah forest).

There are many concerns however. No experienced forester would guarantee the long term viability of dense forest stands growing on a film of topsoil over highly impermeable clay and granite. Jarrah prefers deep friable gravels with excellent water-holding capacity. Where thin, heavy soils occur in the natural forest, jarrah tends to be replaced by wandoo and on shallow soils over granite it is more common to find sheoak. The oldest minesite rehabilitation is now about 40. Some of these stands have started to look very sick as the present period of below-average rainfall persists. Ecologically, the revegetation is very different from the original forest, and some obvious niches have been eliminated. For example no “habitat” trees are retained to provide for hollow-nesting bird species, as is the case in areas from which timber is cut. Some “old growth” elements, such as grass trees, will take centuries to re-establish, or may never regrow on the new substrate.

Apart from the loss of native forest, there has been a significant loss of run-off into streams and dams in the mined-over catchment areas. Pits have been designed to retain rather than shed rainfall, so run-off to forest streams is close to zero, and in many cases old mine pits cover nearly 50% of each sub-catchment. This has obvious impacts on water resources and aquatic ecosystems. The revegetated mine pits also represent a challenge to bushfire management. Although the young rehabilitation (up to about age 4) will generally not carry a fire, litter and flammable understorey soon begin to build up and the new plantations are extremely hazardous and vulnerable to fire over the next 10 years.

There are other environmental concerns. Alumina refineries produce toxic waste (soil contaminated with caustic soda) and both the refineries and aluminium smelters are significant consumers of electricity and emitters of greenhouse gasses. Bauxite miners are exempt from the requirements of both the State’s Wildlife Conservation Act and the Clearing Control Legislation. These Acts can severely constrain landowners who wish to carry out commercial timber production in their own native forest, or to undertake prescribed burning for bushfire remediation (which the government includes within the definition of “clearing”).

Given their fierce opposition to the comparatively benign and ephemeral impacts of timber cutting and prescribed burning, it might be expected that environmentalists and green bureaucrats would be dying in their boots to oppose and hamstring bauxite mining in the jarrah forest. This has not occurred. For over 30 years the alumina industry has enjoyed total freedom from green displeasure and support from conservation bodies – including the Environmental Protection Authority. None of the standard features of a protest campaign against logging, for example, have ever been seen. There are no protest camps in the bush. No students or yuppy celebrities are chained to trees. Mining equipment has not been vandalised, ore trains have not been derailed, haul roads blockaded or port facilities bombed (all features of the campaign against woodchipping). There are there no marches on parliament, no orchestrated campaigns of letters to the paper and call-ins to the talk-back stations. Senator Bob Brown does not appear to have voiced the merest concern. The WA Greens Party has no policy about bauxite mining in the jarrah forest. They seek to prohibit mining and exploration in national parks, wilderness areas and conservation reserves, but do not extend this policy to State Forests. Nor has Janet Woollard (who was elected to the WA Parliament representing a Save-the-Forests party) taken any position on bauxite mining in the jarrah forest. Even the ABC’s Four Corners has shown no interest. Normally they would find irresistible a story about destruction of Australian forests by big business, especially in an industry which is such a significant contributor to greenhouse gas emissions and is American-owned. Instead they are down in Tasmania fulminating against timber production and plantations.

I am not anti-mining. However as a forester I wish the alumina industry would go elsewhere. Nor am I anti-Alcoa. I have always found them to be an efficient and clever organisation, and it is a pleasure to see the professional way in which they have approached their operational and research obligations. They have poured multi-millions of dollars into the WA community over the years, including generous donations to conservation groups, cash payments to government departments, grants to sporting bodies, sponsorship of the arts, dispensing free tree seedlings to farmers and funding academics in the universities.

The uncritical and universal acceptance of bauxite mining in the jarrah forest is disappointing, but not difficult to understand. The government clearly believes that the economic returns from bauxite mining and alumina refining justify the impact on the forest and other forest uses. The broader community has no understanding of what is going on, since the media is silent, and in any case there has never been any public affection for the jarrah forest in the way there has been for the more visually attractive karri forest.

There are two possible reasons why the environmentalists have chosen not to fight bauxite mining: (i) they have been bought off; or (ii) they have decided that it is a battle they cannot win. The latter is the most likely. The alumina industry well-established and prosperous, is fully supported by government agencies, and has a superb public relations machine. The environmentalists would be done over, and they know it. It would be different if 1000 ha of native forest each year were being destroyed for cattle grazing, timber plantations, or water resource development, all of which are easy targets – any protest campaign against them would attract strong media support, especially from the ABC.

Despite environmentalist and community apathy, my personal view is that there will come a time in the not-too-distant future when West Australians realise what has gone on, and the extent and cost of the ecological damage which has occurred. Then perhaps they will look back on the government, agency and NGO-supported destruction of the jarrah forest by bauxite mining as one of the greatest conservation blunders in our history.

Roger Underwood is a former General Manager of CALM in Western Australia, a regional and district manager, a research manager and bushfire specialist. Roger currently directs a consultancy practice with a focus on bushfire management. He lives in Perth, Western Australia.