Your credit card can help save the planet.

That's the message companies are pitching to consumers as they roll out new credit cards designed to cash in on people's worries about global warming.

These "green" cards allow users to channel a percentage of their spending toward efforts to cut greenhouse-gas emissions. General Electric Co.'s Earth Rewards MasterCard, launched in July by the company's GE Money unit, targets as much as 1% of total spending on the card toward emission-reduction projects.Bank of America Corp. followed in November with its own green card, Brighter Planet Visa, which matches every dollar spent with one point that can be accumulated and traded in for "carbon offsets." Carbon offsets are meant to reduce the impact of emissions made somewhere else -- such as by planting trees. Additionally, Storm Lake, Iowa, savings bank MetaBank, a unit of Meta Financial Group Inc., in August launched its GreenPay MasterCard, which also allows users to accumulate carbon offsets with each purchase.

With the Bank of America card, accumulated offsets are funneled to various projects its partner, Burlington, Vt., start-up Brighter Planets, deems deserving. Each month, cardholders will be notified how many carbon emissions have been mitigated with their contributions. With the MetaBank card, individuals earn offsets that they can then use to mitigate their own carbon footprints.

Yet offsets have recently come under criticism in the U.S., where the market is strictly voluntary. Environmentalists are calling for greater transparency in terms of verifying green projects that are eligible for offsets. Some critics charge that offsets don't serve to reduce overall emissions, and should be the last resort for companies and individuals.

Green cards have been available in Europe for several years and have attracted a sizable following, tapping into the region's well-established environmental movement. Their move into the U.S. comes amid mounting concerns over climate change and impending mandatory restriction on carbon emissions.

By some measures, though, the new cards aren't as generous as standard cash-back cards, some of which pay back the card user up to 3% of total spending. By contrast, the environmental cards contribute less than 2% of purchases to green initiatives.

For financial institutions, adding green cards to their product lines is a way to boost their own corporate environmental credentials. Last year, Bank of America and Citigroup Inc. each committed to spend tens of billions of dollars to reduce their own corporate carbon emissions, invest in alternative-energy projects and develop financial products to support their clients' efforts to address these issues.

How Green Is 'Too Green'?

However, banks have moved more slowly to roll out green consumer products. That's because "you can't just tell your customers what to do," says Matthew Arnold of Sustainable Finance, an environmental consulting firm that advises banks. Banks are nervous about issuing environmentally focused cards amid concern about appearing to be "too green" or "judgmental of their customers' behavior," he says.

The credit cards resemble so-called affinity cards -- which are branded with, say, the holder's university, a sports organization or a favorite charity. Affinity cards, which have been around since the 1980s, typically pass along 1% to 1.5% of the value of each card transaction to the cardholder's preferred group.

Comparing the relative merits of the green cards can be tricky, since they use different ways of calculating rewards. But the interest rates they charge do vary. Brighter Planet, the Bank of America card, offers the lowest rate among the three: a fixed annual percentage rate of 9.99% for the most creditworthy applicants, which is lower than the average 11.97% on fixed-rate cards among the 50 largest issuers, according to Bankrate.com.

MetaBank's GreenPay charges 13.25% for all cardholders, while GE charges variable rates that recently ranged from 12.99% to 18.99%, depending on the holder's creditworthiness, according to the card's Web site. That makes it the least competitive among the three. (The average variable rate is 13.1% for people with good credit, according to Bankrate.com.)

Experts say it's generally tough to assess which rewards cards offer the most bang for the buck. The simplest way to compare the green cards "is to convert them back to cash-back," says Curtis Arnold, founder of CardRatings.com, a credit-card rating Web site.

Splitting the Rewards

With GE's program, cardholders earn 1% on each purchase -- the equivalent of 1% cash back -- to fund greenhouse-gas emissions-reduction projects at GE AES Greenhouse Gas Services, a joint venture with power producer AES Corp. Cardholders can also choose to split the rewards equally between carbon credits and cash back. The points are redeemed annually, on Earth Day.

Some may question whether the GE AES joint venture is essentially benefiting from cardholders' money. "The credit card is one avenue for the business of the joint venture; it's not the only one," says a GE spokesman.

Bank of America, by contrast, offers to offset one U.S. ton of carbon emissions for every $1,000 cardholders spend. Brighter Planet, the bank's partner on this product, says the price of carbon offsets averages $10 to $12 per ton, which translates into a cash-back rate of around 1%, according to Mr. Arnold. Additionally, Bank of America will be matching 50% of awarded points through the end of this year, bringing the total reward to 1.5%.

MetaBank's GreenPay card also comes in around the 1% level, according to Mr. Arnold. It offers 1.6% carbon-offset rewards on purchases of gasoline and household utilities, and 0.8% on others. The card buys carbon offsets from the Chicago Climate Exchange, a voluntary greenhouse-gas-emission trading system, where carbon offsets trade around $2 per ton, a deep discount from retail prices. As a result, the card offers about twice the amount of carbon offsets as the other two cards.

'Carbon-Ridiculous'

Some advocates question whether the green cards will actually lead to fewer greenhouse-gas emissions. "What I am more concerned about is that it gives people an easy pass: 'OK, I've got my green credit card, so I can do things that are carbon-ridiculous,'" says Leslie Lowe, director of the Interfaith Center on Corporate Responsibility on Energy and Environment, a nonprofit based in New York.

The card issuers, for their part, say their products can make a difference. "We don't pretend to be the only answer," says Michael Rhodes, senior vice president of Bank of America's North America Card Services. The issuers also offer online calculators for consumers to assess their own household's contributions to greenhouse-gas emissions, and tips on how to reduce that impact.

Card companies are also looking for ways to encourage a greener lifestyle. Sustainable Finance's Mr. Arnold says there are currently a few cards under development that will help customers identify "green" choices within various product categories and let them accumulate rewards points by making more energy-efficient purchases.

Greenwash is a relatively new term that has started springing up in various publications and across mainstream media. According to Wikipedia, greenwash is the act of misleading consumers regarding the environmental practices of a company or the environmental benefits of a product or service.

In December 2007, TerraChoice, an environmental marketing company in North America, released the findings of a study titled 'The Six Sins of Greenwashing'. The company, a leader in green marketing, found that 99% of the 1018 common 'environmentally friendly' consumer products randomly surveyed for the study were guilty of greenwashing.

The findings of the report were alarming and from it the company created the six sins of greenwashing, which it believes will help equip consumers with the tools to figure out the truth about environmentally friendly products.

• Sin of the Hidden Trade-Off: eg, 'Energy-efficient' electronics that contain hazardous materials. 998 products and 57% of all environmental claims committed this sin.
• Sin of No Proof: eg, Shampoos claiming to be 'certified organic', but with no verifiable certification. 454 products and 26% of environmental claims committed this sin.
• Sin of Vagueness: eg, Products claiming to be 100% natural when many naturally occurring substances are hazardous, like arsenic and formaldehyde. Seen in 196 products or 11% of environmental claims.
• Sin of Irrelevance: eg, Products claiming to be CFC-free, even though CFCs were banned 20 years ago. This sin was seen in 78 products and 4% of environmental claims.
• Sin of Fibbing: eg, Products falsely claiming to be certified by an internationally recognised environmental standard like EcoLogo, Energy Star or Green Seal. Found in 10 products or less than 1% of environmental claims.
• Sin of Lesser of Two Evils: eg, Organic cigarettes or 'environmentally friendly' pesticides - this occurred in 17 products or 1% of environmental claims.

In Australia, organisations like the Total Environmental Centre (TEC) are similar in that it monitors claims by companies and organisations that promote themselves as 'green'. Established in 1972 and with over 100 successful campaigns under its belt, TEC's executive director Jeff Angel says it's necessary to have watchdogs because government can move too slowly and be constrained by political links to vested interests.

In 2006, the TEC was concerned that Energy Australia was making representations on its website and in promotional material that its ClearAir and GreenFuture products would provide "100% green electricity at no extra cost" and "100% renewable energy".

A related representation was that "for every kilowatt hour of electricity you buy, the same amount of electricity will be generated from 100% renewable sources, and that's guaranteed", which TEC says were simply false claims. The ACCC investigated Energy Australia's claims after a complaint was received from the TEC.

Whilst Energy Australia withdrew the products from the market in 2006, the ACCC was concerned that Energy Australia's representations may have led consumers to believe that by signing up to the non-accredited ClearAir and GreenFuture products, they would be making equal or similar contributions to renewable energy generation as accredited renewable energy products when this was not the case.

The ACCC was also concerned that consumers may have believed that one environmental benefit of opting to receive these products was that less electricity would be generated from fossil fuels when in reality Energy Australia was acquiring renewable energy credits from existing rather than new renewable energy generation.

"It's been very misleading. We have received many complaints and expressions of confusion. People want to make a difference but instead they have been tricked into thinking the green electricity product would make a 100% change in emissions, when it was very little," says Angel.

Since the investigation, Energy Australia has written brochures outlining to existing customers the differences between environmental accredited and fully accredited 100% Green Power products and the environmental benefits of both.

Angel says that when the need arises, like the case with Energy Australia, TEC works closely with the ACCC and believes it's inevitable that we will see more misleading claims by companies that promote their green products and credentials. "Most recently they [ACCC] have been consulting with a wide range of stakeholders, including TEC, about carbon offset and neutral products." TEC say that it will continue to watch out for greenwashing by Australian companies. "We are continuing with our Green Electricity Watch, along with undertaking a rating survey of carbon offset products which are experiencing multimillion dollar growth. Also, our Green Capital program is likely to have a major greenwashing debate later this year," he says.

A country’s Ecological Footprint is determined by its population, the amount consumed by its average resident, and the resource intensity used in providing the goods and services consumed.

It includes the area required to meet people’s consumption from cropland (food, animal feed, fibre, and oil); grassland and pasture (grazing of animals for meat, hides, wool, and milk); fishing grounds (fish and seafood); and forest (wood, wood fibre, pulp, and fuelwood).

It also estimates the area required to absorb the CO2 released when fossil fuels are burned, less the amount taken up by the oceans. The footprint of nuclear power, about 4% of the global footprint, is included by estimating the footprint for the equivalent amount of energy from fossil fuels.

The area used for a country’s infrastructure, including hydropower, is included as the built-up land footprint component. A country’s biocapacity is a function of the number and type of biologically productive hectares within its borders, and their average yields.

More intensive management can boost yields, but if additional resources are used this also increases the footprint. In the map above, each country’s size represents its share of the global Ecological Footprint.

The colour of each country indicates the per capita footprint of its citizens. Countries with ecological deficits use more biocapacity than they control within their own territories. Ecological creditor countries have footprints smaller than their own biocapacity.

The Living Planet Index measures trends in the Earth’s biological diversity It tracks populations of 1,313 vertebrate species - fish, amphibians, reptiles, birds, mammals - from all around the world.

Separate indices are produced for terrestrial, marine, and freshwater species, and the three trends are then averaged to create an aggregated index.

Although vertebrates represent only a fraction of known species, it is assumed that trends in their populations are typical of biodiversity overall. By tracking wild species, the Living Planet Index is also monitoring the health of ecosystems. Between 1970 and 2003, the index fell by about 30%.

This global trend suggests that we are degrading natural ecosystems at a rate unprecedented in human history.

The sunscreen that you dutifully slather on before a swim on the beach may be protecting your body—but a new study finds that the chemicals are also killing coral reefs worldwide.

Four commonly found sunscreen ingredients can awaken dormant viruses in the symbiotic algae called zooxanthellae that live inside reef-building coral species.

Global Warming Has Devastating Effect on Coral Reefs, Study Shows (May 16, 2006) The chemicals cause the viruses to replicate until their algae hosts explode, spilling viruses into the surrounding seawater, where they can infect neighboring coral communities.

Zooxanthellae provide coral with food energy through photosynthesis and contribute to the organisms' vibrant color. Without them, the coral "bleaches"—turns white—and dies.

"The algae that live in the coral tissue and feed these animals explode or are just released by the tissue, thus leaving naked the skeleton of the coral," said study leader Roberto Danovaro of the Polytechnic University of Marche in Italy.

The researchers estimate that 4,000 to 6,000 metric tons of sunscreen wash off swimmers annually in oceans worldwide, and that up to 10 percent of coral reefs are threatened by sunscreen-induced bleaching. The study appeared online in the journal Environmental Health Perspectives.

Activated Viruses

Danovaro and his team studied the effects of sunscreen exposure on coral samples from reefs in the Pacific, Atlantic, and Indian Oceans. Even low levels of sunscreen, at or below the typical amount used by swimmers, could activate the algae viruses and completely bleach coral in just four days, the results showed.

Seawater surrounding coral exposed to sunscreen contained up to 15 times more viruses than unexposed samples. Several brands of popular sunscreens were tested and all had four ingredients in common: paraben, cinnamate, benzophenone, and a camphor derivative.

Dangerous Dose

Robert van Woesik, a coral expert at the Florida Institute of Technology, was not involved in the research. Global Warming Has Devastating Effect on Coral Reefs, Study Shows (May 16, 2006) He questions whether conditions in the study accurately reflect those found in nature.

For example, the coral samples were exposed to sunscreen while in plastic bags to avoid contaminating the reefs. But van Woesik worries this prevented dilution of the chemicals through natural water circulation. "Under normal situations on a coral reef, corals would not be subjected to these high concentrations because of rapid dilution," van Woesik said.

But according to study author Danovaro, the effect is not dose dependent—so coral's exposure to a very small dose of sunscreen is just as dangerous as a high exposure. "It is more like on-off," he said. "Once the viral epidemic is started, it is not a problem of toxicity."

Alarming Trend

Rebecca Vega Thurber, a marine virus and coral researcher at San Diego State University in California, said the new results are further evidence of an alarming trend. "Other [human-induced] factors such as coastal pollution, overfishing, and sedimentation all contribute to coral reef habitat degradation, and this work continues in that vein," said Vega Thurber, who was also not involved in the research. "But before we ban sunscreens, we must first determine if local ambient concentrations of sunscreens are positively correlated with coral bleaching events."

Danovaro says banning sunscreen won't be necessary, and points out two simple things swimmers can do to reduce their impact on coral:

• Use sunscreens with physical filters, which reflect instead of absorb ultraviolet radiation
• use eco-friendly chemical sunscreens.