People are being urged to join UK landmarks as they switch off their lights for an hour on Saturday night to back action on climate change.
Climate Change Focus Of Election Campaign Trail
Political parties will focus on how they will tackle climate change as campaigning for May's Holyrood election continues.
Candidates from the five main parties will be grilled on their environmental policies in a debate in Edinburgh hosted by the Stop Climate Chaos Scotland coalition.
Climate change will also be on the agenda at the Scottish Trades Union Congress (STUC) annual gathering in Dundee, where trade unions will call for strong action and support for workers affected by a switch to a low-carbon economy.
The SNP will launch its manifesto on Wednesday with a pledge to raise Scotland's 2020 climate target from the current 42% cut in carbon emissions to more than 50%.
Opposition parties have highlighted that the current target has been missed in each of the last four years.
Scottish Labour leader Kezia Dugdale said her party would ban fracking, cancel SNP plans to cut air passenger duty and introduce legislation to tackle fuel poverty by toughening up energy and insulation standards.
Ms Dugdale said: "The SNP's approach to climate change is similar to its whole approach to government - set a target, miss it and then set an even tougher target in the hope nobody notices.''
The Scottish Liberal Democrats also back a ban on fracking as well as open-cast coal mining.
Energy spokesman Liam McArthur said: "Our main priority is improving the energy efficiency of Scotland's homes.
"We're also focusing on boosting renewable heat and electricity generation in new and innovative ways. We will adopt the first ever industrial heat strategy and use geothermal heat from disused coal mines.''
Stop Climate Chaos Scotland chair Tom Ballantine said: ``The next Scottish Parliament, whatever its political make-up, must ensure that delivering on the Climate Act is at the top of their agenda.
"We are already seeing the impacts of climate change with-record breaking temperatures each year and extreme weather events like storms and flooding. Action to cut carbon emissions is needed urgently.''
Stephen Boyd, STUC assistant secretary, said: "Addressing climate change can deliver significant economic, social and environmental benefits to Scotland.
"Planning for a just transition means we involve all parts of society, sharing these benefits and supporting those whose jobs are affected, with education, training, skills and workforce development also crucial to delivering effective action.''
Elsewhere on the election trail, SNP leader Nicola Sturgeon will highlight her party's policies for newborns and their parents on a campaign visit in the Glasgow Cathcart constituency with candidate James Dornan.
The First Minister will say: "am determined that every child born in Scotland gets the very best start in life and have made clear my ambition that all children should have the same chance to fulfil their potential.''
The Scottish Conservatives have accused the SNP government of ``burying bad news'' by not publishing the latest figures on revenue generated by Scotland's stamp duty replacement, the Land and Buildings Transaction Tax.
Party leader Ruth Davidson said: "These figures were published regularly at the end of each month for the last 11 months. Why suddenly the silence now?''
"Our own calculations suggest that the SNP's black hole is between #38 million and #42 million. If the SNP wants to challenge that then it knows how - stop hiding the facts, and publish the truth."
Meanwhile Scottish Liberal Democrat leader Willie Rennie will visit a farm in Fife to highlight delays in European Union support payments to farmers.
A former youth football scout has been arrested by police investigating allegations of historical abuse in the sport.
Police are investigating whether purple pills found in Fife are connected to a case in which a teenage boy fell ill.
A Royal Navy helicopter pilot has paid a flying visit to his former aircraft to see its transformation into an unusual holiday home near Stirling.
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