Are lowcost airlines affecting the climate?

It seems that flying lowcost has increased the percentage of gas emissions in europe!!

Travelling with just 50 euros across europe is a great thing confronting with prices of traditional airlines...but there's a catch.
All these flight have impact, a big one in our skies. The success of low-cost airlines threatens to ruin all European efforts to reduce greenhouse gas emissions. Consequently, the call for an EU-wide tax on aeroplane fuel is getting louder. Probably this isn't a great solution...
People will and must continue to travel across this continent so just putting a tax to collect money or to "advise" not to travel isn'r so great, instead of searching other solutions, like other fuels or easier other means of trasportation..

Low-cost airlines are conquering the European travel market with cut-throat prices, and the aeroplane is fast becoming an everyday means of transport. But this has dramatic consequences for the environment as no other form of transport has such a damaging ecological effect as the aeroplane. A single flight can use up to five times as much fuel as a train journey of the same distance. Even the car, with a similar fuel consumption per head, is better in comparison. But most important...........at such high altitude, the combustion of fuel contributes to the greenhouse effect to a far greater extent than on land.

So, can flight become more greener, more ecological friendly?
I admit myself used several times lowcost flight, paid little and had fun, but....what is the real price actually?

Also...the airlines woo customers away from alternative forms of transport – according to one survey, a third of Ryanair’s customers (the biggest low-cost airline) have switched from car or train because of the low prices. The budget airlines have created a completely new mass market. A two day shopping trip to London and a relaxing weekend in Mallorca would remain a luxury few could afford without Ryanair and Co.