Barclays on Thursday launched 11 new exchange-traded notes through its iPaths lineup, including a much-anticipated fund tracking carbon emissions.

Others have also been racing to get a similar alternative energy ETF or ETN out the door. But the notes, underwritten by the giant London-based bank, has gained first-mover status in what no doubt will be a hotly contested field.

Linked to the Barclays Capital Global Carbon Index Total Return, the iPath Global Carbon ETN (NYSE Arca: GRN) is the first ETN designed to provide investors with exposure to the global price of carbon.

With global warming gaining increasing attention and being addressed with new urgency, indexes are being created to capture the market for trading carbon in world markets.

Such so-called carbon emission credits are traded by companies who get tax breaks and other incentives for lowering pollutants into the air. These standards are designed to set limits on the amount of a pollutant that can be released into the atmosphere and allocates credits among companies creating emissions. Those that do not use all their emissions credits can sell them to companies that need them.

By some estimates, the global carbon market is worth more than $50 billion a year.

XShares has in registration an exchange-traded fund to invest in futures contracts traded in the European Union based on carbon emissions allowances.

Besides GRN, the 10 others introduced carve up the Dow Jones-AIG Commodity Index Total Return into subsectors:

• iPath Dow Jones-AIG Tin Total Return Sub-Index ETN (NYSE Arca: JJT)

• iPath Dow Jones-AIG Sugar Total Return Sub-Index ETN (NYSE Arca: SGG)

• iPath Dow Jones-AIG Softs Total Return Sub-Index ETN (NYSE Arca: JJS)

• iPath Dow Jones-AIG Precious Metals Total Return Sub-Index ETN (NYSE Arca: JJP)

• iPath Dow Jones-AIG Platinum ETN Total Return Sub-Index (NYSE Arca: PG)

• iPath Dow Jones-AIG Lead ETN Total Return Sub-Index (NYSE Arca: LD)

• iPath Dow Jones-AIG Cotton Total Return Sub-Index ETN (NYSE Arca: BAL)

• iPath Dow Jones-AIG Coffee Total Return Sub-Index ETN (NYSE Arca: JO)

• iPath Dow Jones-AIG Cocoa Total Return Sub-Index ETN (NYSE Arca: NIB)

• iPath Dow Jones-AIG Aluminum Total Return Sub-Index ETN (NYSE Arca: JJU)