China’s spectacular economic growth during the last decade has brought many benefits – and some challenges. Global atmospheric mapping of nitrogen dioxide pollution performed by ERS-2’s GOME and Envisat’s SCIAMACHY reveals the world’s largest amount of NO2 hanging above Beijing and northeast China, as reported in Nature this week.

As part of ESA’s Dragon Programme, European and Chinese researchers are using results returned from the Global Ozone Mapping Experiment (GOME) on ERS-2 and the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) on Envisat to monitor and forecast Chinese air quality.

In this context, researchers at the University of Bremen, the Max-Planck Institute of Meteorology in Hamburg and France’s Centre National de la Recherche Scientifique (CNRS) have been studying the retrieval of nitrogen dioxide variability from space and modelling its global behaviour.

The team have published an article in the 1 September 2005 edition of the science journal Nature about the global changes in nitrogen dioxide observed in the last decade from space and highlighted the dramatic changes over China.

Nitrogen dioxide (NO2) is associated with nitrogen oxide (NO2) in the atmosphere and the sum of the two is called NOX. This is released into the troposphere from power plants, heavy industry and road transport, along with biomass burning, lightning in the atmosphere and microbial activity in the soil. The emission of nitrogen oxides has increased about six-fold since pre-industrial times and in cities above a thousand times more NOX is present than in the pristine and remote marine boundary layer.

Exposure to nitrogen dioxide in large quantities is known to cause lung damage and respiratory problems, although little is known about the consequences of long term exposure to elevated atmospheric amounts. The presence of this gas is a significant driver of the production of low-level ozone, which, within the troposphere (the lowest part of the atmosphere, extending eight to 16 kilometres in height) is itself a harmful toxic pollutant, a major ingredient of photochemical smog.

“While nitrogen dioxide vertical column concentrations above central and eastern Europe and parts of the East Coast of the United States have been either static or exhibiting a small decrease, there is a clear and significant increase over China,” explains John Burrows of the University of Bremen’s Institute of Environmental Physics, SCIAMACHY’s Principal Investigator.

“Before SCIAMACHY was flying we previously retrieved NO2 data from its precursor instrument, GOME on ESA’s ERS-2 mission. Although GOME had lower resolution, the article shows that China’s nitrogen dioxide retrievals from the two instruments overlap seamlessly.

“What the combined data show are that nitrogen dioxide levels have risen by around 50% since 1996, and this behaviour is continuing.”

Space-based sensors are the only way to carry out effective global and regional monitoring of the atmosphere. While GOME demonstrated the first satellite sensitivity to tropospheric nitrogen dioxide, SCIAMACHY possesses superior performance, with a spatial resolution of 60 x 30 kilometres compared to 320 x 40 km for its predecessor.

SCIAMACHY also observes the atmosphere in two different ways – downwards or nadir-sounding’ as well as ‘limb-sounding’ along the direction of flight – and with a larger spectral range than its predecessor.

The increase in nitrogen dioxide levels seen is an unfortunate side effect of economic success. China’s industrial boom has seen it become the world’s largest consumer of copper, aluminium and cement and the second bigger importer of oil. Car ownership within the country has been doubling every few years.

“China’s nitrogen dioxide concentration varies according to season,” Burrows adds. “There is more in the winter as a result of differing emission patterns and meteorology. For example more fuel is burned for heating and nitrogen dioxide persists longer in the atmosphere at that less sunny time of year – lasting around a day rather than hours, as in the summer.

“Meteorology also plays a role. There is a peak before Christmas: this is not because industrial activity, domestic heating or transportation is suddenly reduced after the holiday season but because there is an eastward outflow of air that was previously revolving around Asia. This is the same type of phenomenon that carries dust from the Gobi Desert across to the West Coast of the US.”

China is reliant on coal to meet 75% of its national energy needs, and that means high levels of another atmospheric pollutant called sulphur dioxide (SO2) also detectable by SCIAMACHY. Large SO2 sources over China that overlap with nitrogen dioxide plumes are linked to power plants. Further to the west there is also sulphur dioxide produced from smouldering underground coal seam fires.

Burrows is the scientist who – supported by an international team – proposed both GOME and SCIAMACHY to national space agencies and ESA in the first place. He explained that the two instruments were originally chosen to fly because of their ability to measure stratospheric ozone, but were also selected in order to investigate the amount of useful information that could be retrieved from the troposphere.

“The instruments are now being used to monitor a significant number of key tropospheric trace gases including formaldehyde, methane, sulphur dioxide and carbon monoxide and dioxide,” Burrows remembers. “Back when we were starting out, many people thought it would be impossible to get any useful results out of the troposphere. There are many important issues to deal with, such as cloud cover and the highly variable reflectivity of the surface, as well as having the absorption or emission of stratospheric and upper atmospheric species situated between the troposphere and the instrument.

“First with GOME and now much better with SCIAMACHY we are demonstrating it can be done. The success so far is an important step on the way to establishing an operational global observing system for the Earth’s atmosphere. This is something we need as we enter the geological age of the Anthropocene, where the activities of mankind and its interactions with natural phenomena are the driving force in global climate change.

“Next we are hoping for follow-up satellite missions, in particular from geostationary orbit to monitor atmospheric pollution, which has a strong diurnal variation and thereby determine objectively the changing atmospheric composition.”

SCIAMACHY: surveying the world in six days

SCIAMACHY is a spectrometer, and it works by measuring sunlight – either transmitted, reflected or scattered by the Earth’s atmosphere or surface in the ultraviolet, visible and near infrared regions. Mathematical inversion of these data yields the amounts and distribution of trace gases, ozone and related chemicals, clouds and dust particles throughout the atmosphere. With a 960-km swath and alternate limb and nadir observations, SCIAMACHY covers the entire world every six days at the equator and more often at high latitudes.

This versatile instrument represents a national contribution to ESA’s Envisat mission. It was funded by the German government through the German Aerospace Center (DLR), the Dutch government through the Netherlands Agency for Aerospace Programmes (NIVR) and also the Belgian government through the Belgian Institute for Space Aeronomy (BIRA-IASB).

SCIAMACHY is part of a family of atmospheric sounders that also includes GOME on ERS-2 and also the forthcoming GOME-2 instrument due to launch next year aboard ESA’s and EUMETSAT’s first MetOp spacecraft.

About Dragon

The Dragon Programme is a joint undertaking between ESA, the Ministry of Science and Technology (MOST) of China and the National Remote Sensing Centre of China (NRSCC). Its purpose is to encourage increased exploitation of ESA space resources within China as well as stimulate increased scientific co-operation in the field of Earth Observation science and applications between China and Europe.

Original press release: Breath of the dragon: ERS-2 and Envisat Reveal Impact of Economic Growth on China’s Air Quality (ESA)

As the European Commission is preparing a new EU Directive on flood risk management, WWF asks that lessons be learnt from the repeated catastrophic flood events across Europe.

While only 20 per cent of Europe’s natural floodplains are estimated to be still functional and thus able to store water, the global conservation organization says that the only sustainable solution to reduce the risk of further devastating floods is to work with nature, rather than against it.

Parts of Europe were flooded once more this summer and WWF deeply regrets the suffering this has caused, in particular in the Alps and the lower Danube region. Floods are a natural phenomenon that cannot be avoided, but their frequency and intensity is growing due to global warming and climate change. Still, the damage they inflict can be limited, but traditional old-fashioned, engineering solutions for flood protection have proven not to work without additional measures.

“The latest events clearly demonstrate that we cannot control floods of such magnitude with technical means alone,” said Tatjana Brombach, ecoregional leader with WWF’s European Alpine Programme.

“Building in areas at flood risk just increases the danger of future flooding as even recent flood defence engineering works, such as the Pflach dam in the Austrian Alps that broke this summer, have been shown to be alarmingly vulnerable. The only long-term solution is to reconsider the value of nature to help dealing with torrential rains.”

Land and water have a “natural” role to play in flood risk management via, for example, water retention by floodplains and wetlands. These can act as sponges, absorbing and retaining floodwaters to slowly release them afterwards. However, having been disconnected from their rivers, drained and in many cases used intensively by humans, floodplains and wetlands do not play this role anymore. Broad riverbeds can absorb high water flows, but rivers are now narrower because they have been turned into canals. Consequently, flooding impacts are exacerbated, as floodwaters have nowhere to go and rise above the level of artificial riverbanks and/or break through dykes, causing enormous damage.

For years now, WWF has called on the EU and its Member States to change their strategy for flood risk management and work with nature. The EU already has laws that could promote natural flood risk reduction, in particular the 2000 Water Framework Directive. Its implementation requires the joint management of all land and waters making up a river basin, including in cross-border regions, to improve upon its ecological condition.

This would demand improved land-use and forest management, providing more space for riverbeds and making upland wetlands and lowland floodplains functional again, thus reducing flooding.

The European Commission is now developing a Directive dealing specifically with the risks of flooding.

“But natural flood control will not be promoted unless new flood risk reduction measures are part of the Water Framework Directive river basin management plans,” said WWF European Water Policy Officer Eva Royo Gelabert.

“Unfortunately, preparatory documents indicate that this level of integration between the two Directives is not foreseen, there is not even compatibility in their implementation timetables.”

WWF is asking the Commission to reconsider this in order to ensure legal consistency between these Directives, avoid doubling administrative efforts, save money, and then effectively protect people.

Furthermore, WWF calls for EU financial support to the affected regions through, for example, the EU Solidarity and Rural Development Funds to also ensure long-term solutions to resolve the inadequate land-use and water management policies that have contributed to these terrible flood events.

Original press release: Work With Nature, Not Against it to Reduce Risk of Floods in Europe (WWF)

Climate change will wreak havoc on the United Kingdom’s marine environment, deepening the decline of cod, threatening the future survival of some sea bird colonies, and causing wide-scale coastal disruption, a new WWF report has found.

The report — Climate change: Plunging our Seas into Deeper Crisis — notes that an increase in sea surface temperature will be a major factor in further disrupting the breeding, feeding, and growing cycles of fish, and in turn sea birds. This will be spurred by impacts on plankton, the major food source of many fish and the foundation of the entire marine environment.

The report also found that major storm surges — temporary increases in sea level caused by atmospheric pressures and strong winds — will have destructive impacts on coastal areas as they become more frequent. Storm surges could cause flooding events in the east of England and in the London area. Sea level rise is also likely to reduce coastal habitats of sea birds through erosion and damage to nesting sites. Sandeels, a major food source for birds and fish, which breed in shallow sand banks, may also be affected.

“Our seas are already under severe pressure from a number of activities such as fishing, oil and gas exploration, and coastal development,” said Andrew Lee, Director of Campaigns at WWF-UK.

“This report shows that climate change has the power to deepen this crisis and to completely turn our marine world upside down, disrupting and changing the entire ecosystem.”

The North Sea, where plankton is reported to have already changed dramatically, is likely to be hit the hardest by climate change. This will have direct impacts on cod stocks, in addition to the existing pressures from fisheries, according to the report.

“This heightens the urgency for government action to both significantly reduce the UK’s CO2 emissions and to bring forward a new Marine Bill, which will protect our marine wildlife and reform the way our seas are planned and managed to ensure they are economically productive and sustainable for future generations,” Lee added.

The group of scientists who contributed to the report also highlighted ocean acidification as a major concern. The acidity (pH) of the sea has already reduced from 8.3 to 8.2 and is predicted to decline to 7.6 by the end of the century. This would be beyond any level of acidity experienced by current marine wildlife and is likely to impact corals, sea urchins and shell fish as well as breeding success of fish, such as cod.

Harbour porpoises and fin whales are most likely to be affected by climate change through the combined impacts of pollution and reduced food supply. This will threaten their breeding success, and in the case of harbour porpoises, this is likely to accelerate their decline.

“Climate change will cause dramatic disruption to our seas over the coming years,” said Emily Lewis-Brown, WWF-UK’s Marine Research Officer.

“Future planning of our marine environment must take into account the effects of climate change to help our seas adapt to the challenges that will come.”

Original press release: Climate Change to Cause Chaos in UK Seas (WWF)

NASA is marshaling agency resources to assist Gulf Coast-area facilities that suffered damage from Hurricane Katrina. The agency is preparing to provide help for NASA employees and contractors whose homes were damaged or destroyed.

Monday’s storm hit NASA’s Stennis Space Center in Mississippi and Michoud Assembly Facility in New Orleans, which is operated by Lockheed Martin. Both facilities are closed during recovery efforts. During the storm, hundreds of people including employees, family members and others took shelter at Stennis. A small contingency of NASA employees and contractors rode out the storm at Michoud. There are no reports of any injuries at NASA facilities.

“My heart goes out to all the people affected by this hurricane,” said NASA Administrator Michael Griffin. “I will be visiting Stennis and the Michoud Assembly Facility soon to talk with our people.”

NASA’s Marshall Space Flight Center, Huntsville, Ala., sustained minor damage and is providing support to Stennis and Michoud. Two helicopter flights from Marshall were delivering communication equipment and other supplies to the facilities today. Initial damage assessments indicate some buildings at Stennis sustained water and roof damage, but the exact extent has not been determined.

The Federal Emergency Management Agency is using the center as a staging area for local recovery efforts. The center’s Space Shuttle main engine test stands do not appear to be damaged.

At Michoud, which makes the Space Shuttle’s external fuel tanks, several buildings suffered window and roof damage. It appears that space flight hardware was not damaged, but a preliminary assessment has not been completed. The facility has no electrical power and communication is limited. Debris on roadways is restricting transportation around the facility.

Original press release: NASA Assesses Hurricane Katrina Damage (NASA)

New results shed light on how Antarctica became the icy, barren continent that we know today. British Antarctic Survey (BAS) scientists have discovered that 30-50 million years ago, South America and Antarctica split apart very rapidly. This formed the Drake Passage and resulted in a major global cooling. The findings are published in the latest issue of Earth and Planetary Science Letters.

Lead Author Dr Roy Livermore says ‘we deciphered the remarkable ‘herringbone’ pattern of ridges that were etched into the Earth’s crust beneath the remote Weddell Sea when South America moved away from Antarctica. This revealed that the two continents separated extremely quickly in geological time forming a shallow ‘gateway’ between the Pacific and Atlantic oceans. We estimate that this happened some ten to twenty million years earlier than the previous oldest estimate. Even a shallow (less than 1000 metres) gateway would have had a profound effect on Southern Ocean circulation and subsequently climate”.

Such a gateway, by completing a circuit of water around Antarctica, eventually led to the formation of the Antarctic Circumpolar Current, the world’s largest deep current which now transports some 130 million cubic metres of water through the Drake Passage every second. The effect was to cut Antarctica off from warm southward flowing currents leaving it frozen and desolate.

This new research reinforces findings from deep-sea sediments cores taken from the Southern Ocean and supports the theory that the opening of the Drake Passage could have triggered the abrupt global cooling event and extensive growth of the Antarctic ice sheet 33-34 million years ago.

Original press release: Early Drake Passage Opening Led to Global Change (BAS - British Antarctic Survey)

Real-time radar data and high-tech communications were the keystones to success this past weekend as the Rainband and Intensity Change Experiment (RAINEX) project began its research with Hurricane Katrina. The project is funded by the National Science Foundation (NSF).

RAINEX became the first hurricane research project to fly planes nearly simultaneously inside and outside a hurricane’s principal rainband, gathering information that will help scientists to better understand changes in a hurricane’s intensity.

RAINEX is studying the interaction between hurricane winds and rain, using data recorded from hurricane research flights, according to Steve Nelson, program director in NSF’s atmospheric sciences division, which funded RAINEX. For six weeks of this year’s active hurricane season, two research aircraft will fly simultaneously into hurricanes before the storms make landfall.

Flying in the hurricane’s outer bands and eyewall on most flights, the aircraft are using sophisticated Doppler radar and Global Positioning System dropsondes to record wind speed and direction, temperature, humidity, atmospheric pressure, and other critical data.

“While the forecasting of hurricane tracks has come a long way, that kind of information results from a variety of variables external to the hurricane,” says Robert Houze, an atmospheric scientist at the University of Washington and a RAINEX principal investigator. “Intensity is driven in part by internal dynamics between the rainbands and the eyewall - something that is very hard to get to - so this is landmark information that will help us to understand this phenomenon better.”

Shuyi Chen, a meteorologist and physical oceanographer at the University of Miami Rosenstiel School of Marine and Atmospheric Sciences (RSMAS), also a RAINEX principal investigator, developed a fine-resolution, coupled atmosphere-wave-ocean computer model to study hurricane intensity changes. While most models estimate atmospheric activity down to tens of kilometers, her model goes further - down to a kilometer or two, filling in information gaps and providing realistic rainband and eyewall structure simulation. Researchers are able to use the model in combination with airborne Doppler radar measurements to better understand hurricane intensity changes.

“The airborne radar data come into our operations center in real-time,” said Chen. “We process it, and then share it with the research planes within a few minutes. This helps the planes navigate and position themselves appropriately, and it helps us guide planes to exactly the area of the hurricane where we want to take measurements. It’s the first time we have ever tried this new way of communicating from the ground to planes flying in a hurricane.”

RAINEX also involves scientists from the National Center for Atmospheric Research (NCAR) in Boulder, Colo., the National Oceanic and Atmospheric Administration (NOAA), and the U.S. Navy.

Original press release: Hurricane Katrina: Scientists Fly Into Eye of the Storm (NSF)