An Taisce has called on the Government to include specific emission reduction targets in its climate change legislation.

Addressing the Joint Oireachtas Committee on the Environment, Culture and Gaeltacht, the national trust organisation said without such targets, there is no way to link the intention of the legislation and the final action.

An Taisce was addressing the committee as part of ongoing hearings on the outline heads of the Climate Action and Low-Carbon Development Bill.

The bill aims to set out a framework by which the dangers of carbon emissions and climate change can be addressed, while at the same time ensuring a sustainable environmental and economic future.

The draft laws would place a statutory obligation on Government to adopt and implement plans that enable the state to transition to what the Department of the Environment describes as a low-carbon, climate-resilient and environmentally sustainable economy in the period to 2050.

Within each seven-year period, the Government will have to come up with a fresh road map to reach targets, and a progress report will have to be given to the Dáil each year by the minister.

There will also be an advisory group made up of experts from various State agencies, which will assess and review compliance.

However, An Taisce took issue with the absence of specific carbon emission reduction targets in the document.

Policy Director James Nix told the committee that the expert advisory group, which will have a role in overseeing the implementation of the Government's climate change plan, should have rights to publish its reports independently of the Government.

He also called for the inclusion of a scientist on the advisory board.

Earlier, the Irish Farmers' Association told the committee it acknowledged the decision by Minister for the Environment Phil Hogan that "divisive and unachievable national targets will not be part of future climate strategy".

The IFA said farmers in Ireland are amongst the world's leaders in sustainable emission efficient food production.

It also said it was essential that future climate policy does not stifle the expansion of the agri-food exporting sector.

It said in order to achieve EU targets for carbon reduction from the agriculture, transport and residential sectors by 2020, the purchase of carbon credits will have to be considered.

Professor Ray Bates of the Meteorology and Climate Centre in UCD said most of the global average temperature rise of 0.8C and the average sea level rise of 20cm over the past century are with a high degree of certainty due to human activities, mainly CO2 emissions.

Sea level rises are running at an annual rate of 3.2mm, he said.

Prof Bates said if CO2 emissions continue unabated, these trends will continue, although recent research suggests the rate of global temperature increases may not be as great as previously feared.

He said locally in Ireland much of what appears to be man-made climate change is natural climate change variability.

Prof Bates recommended that greenhouse gases must be reduced to mitigate against the effects of climate change.

He said EU targets already agreed and proposed are already very demanding and Ireland does not need to make additional sacrifices to go beyond these targets.