I am writing from the last day of the UN climate conference COP18 in Doha, Qatar, where heads of state, academics, the business community and civil society have gathered for the high level segment of the 18th UN Conference of Parties. Hopes are not high.
I have committed my life to defending human rights, social justice and the protection of the environment. I was born in Nicaragua, and spent my childhood and adolescence under the brutal and repressive dictatorship of the Somoza regime. I learned first-hand the meaning of oppression and social and economic injustice. I left Nicaragua armed with a scholarship to study political science in Paris.
I founded the Bianca Jagger Human Rights Foundation in 2006 to be a force for change, and a voice for the most vulnerable members of society. The BJHRF is dedicated to defending human rights, achieving social justice, protecting the rights of indigenous peoples, speaking up for future generations and addressing the threat of catastrophic climate change.
Today, we stand at the precipice of various global crises.
The effects of climate change can already be seen in extreme weather events across the world. In 2012 Hurricane Sandy , the typhoon in the Philippines , record flooding in Pakistan  and China,  torrential rains and flooding in El Salvador, Honduras and Nicaragua in 2011 , heat waves in Russia in 2010  the UK in 2009 and 2012; Hurricane Katrina in 2005 .
Last month was the 333rd consecutive month that global temperatures were above the 20th century average .
The atmospheric concentration of CO2 has risen by 31 per cemt since around 1750, when the industrial revolution began . It’s now at the highest levels in 420,000 years . I could go on and on. The science is clear. Climate change is accelerating.
I am concerned about the outcome of COP18. Unfortunately, there is a serious gap between what is being negotiated and what the science requires to keep temperatures under a 2 degree Celsius rise. According to the UNEP Emissions Gap Report  even if the most ambitious current pledges from countries to cut emissions are honoured, the atmosphere will likely still contain eight gigatonnes of CO2 above safe levels.
"Turn Down the Heat: Why a 4° C Warmer World Must be Avoided,"a report commissioned by the World Bank from Potsdam Institute for Climate Impact Research and Climate Analytics, was released in November 2012. The groundbreaking report has changed the discourse among the negotiators and the media here at Cop18 in Doha. It delivers some alarming and long overdue facts, stating, "a 4°C world is so different from the current one that it comes with high uncertainty and new risks that threaten our ability to anticipate and plan for future adaptation needs… The 4°C scenarios are devastating…The inundation of coastal cities; increasing risks for food production potentially leading to higher malnutrition rates; many dry regions becoming dryer, wet regions wetter; unprecedented heat waves in many regions, especially in the tropics; substantially exacerbated water scarcity in many regions; increased frequency of high-intensity tropical cyclones; and irreversible loss of biodiversity, including coral reef systems…"
In 1896, Svante Arrhenius , a Swedish scientist, observed that if CO2 levels continued to rise global temperatures would also rise by around 4 degrees Celsius by the end of the 21st century.
Why has it taken us over a hundred years to come to the same conclusion?
We know that even a few degrees temperature rise will drastically change the habitability of the planet and bring about potentially catastrophic changes in water sources, forests, food, health, business… It will affect cities, rural areas, economies, food security and health; the physical shape of the land and coast, every aspect of our lives throughout the developing and the developed world. Climate change will affect everyone everywhere, in every nation and from every socio-economic group – but not in the same way. Climate change is an issue of social justice.
We are already experiencing dangerous climate change. The task now is to avoid catastrophic climate change.
Not all the news is bad, however. There are concrete steps we can take. One of them is Plant a Pledge.
Plant a Pledge
In May 2012, I was appointed Ambassador for the IUCN Plant a Pledge Campaign.
The aim of Plant a Pledge is to support the Bonn Challenge target, to restore 150 million hectares of degraded and deforested land by 2020. This is the largest restoration initiative the world has ever seen.
The Global Partnership on Forest Landscape Restoration (GPFLR) has mapped 2 billion hectares of deforested and degraded land across the globe - an area the size of South America - with potential for restoration.
The Stern Review  on the Economics of Climate Change recognises that "curbing deforestation is a highly cost-effective way of reducing greenhouse gas emissions." Deforestation constitutes nearly 20 per cent of overall emissions , and is accelerating climate change. The world's forests store 289 gigatonnes of carbon  in their biomass alone, and can be used as a tool to mitigate climate change. Restoring 150 million acres of forest landscapes could sequester approximately 1 gigatonne of carbon dioxide per year. Plant a Pledge, and the Bonn Challenge have never been more relevant.
Restoration of degraded and deforested lands is not simply about planting trees. People and communities are at the heart of the restoration effort, which transforms barren or degraded areas of land into healthy, fertile working landscapes. Restored land can be put to a mosaic of uses such as agriculture, protected wildlife reserves, ecological corridors, regenerated forests, managed plantations, agroforestry systems and river or lakeside plantings to protect waterways.
We launched Plant a Pledge at a press conference at Rio+20 in June 2012, where we announced landmark restoration commitments totalling 18 million hectares. The United States Department of Agriculture Forest Service pledged 15 million hectares, the government of Rwanda 2 million hectares, and the Mata Atlantica Forest Restoration Pact of Brazil, a coalition of government agencies, NGOs and private sector partners 1 million hectares.
I am delighted to announce the pledges of El Salvador and Costa Rica, of 1m hectares each, which brings us to 20 million hectares, and within reach of 50 million.
BMS Rathore, India’s Joint Secretary, Ministry of Environment and Forests, has indicated India’s commitment to the Bonn Challenge, in a pre-pledge of 10 million hectares, at the Convention on Biological Diversity, COP11 in Hyderabad. The Meso-American Alliance of Peoples and Forests has indicated their interest in pledging 20 million hectares. We look forward to them formalising their commitment with the GPFLR and the IUCN.
The success of the campaign, and the number of restoration and reforestation pledges has exceeded all expectations. We’ve far exceeded the target for pledges for 2012, which was 7 million hectares.
But we still need to persuade governments and others who own or manage land around the world to achieve the Bonn Challenge goal by 2020.
The Plant a Pledge campaign aims to do just that. Plant a Pledge was devised by the IUCN and sponsored by Airbus. Each pledge at www.plantapledge.com  supports a global petition directed at world leaders, calls on governments put pen to paper on the specifics – ‘where, when and how?’ – to achieve the Bonn Challenge.
Damage to our forests and ecosystems could reduce global GDP by about 7 per cent and halve living standards for the world's poorest communities by 2050. Forests sustain our most basic needs. They are vital for clean air, food, three-quarters of the world's fresh water, shelter, health and economic development. 1.6 billion people - almost a quarter of the world's population - depend on forests for their livelihood. 300 million people call forests their home.
We urgently need to put public pressure on governments, businesses, big landowners and communities to contribute to the Bonn Challenge target.
At www.plantapledge.com  you can help us push land restoration to the top of the political agenda. This is a unique opportunity to renew our forest landscapes now. Our fate and the fate of future generations depend on it.
Restoration can help lift millions of people out of poverty and inject more than US$80 bn per annum into local and global economies while reducing the gap between the carbon emissions reductions governments have promised and what is needed to avoid dangerous climate change by 11 to 17 per cent. And we will see the benefits not only in our lifetime, but in years to come.
On the eve of the Second World War Winston Churchill  addressed the House of Commons:
"The era of procrastination, of half-measures, of soothing and baffling expedients, of delays, is coming to its close. In its place we are entering a period of consequences."
Today, we are indeed entering a period of consequences. The crises we face are global, and we will only solve them through global collective action. I hope that our leaders will not let us down here at COP18, that they will close that gap between what is being negotiated, and what the science requires. I hope we walk away from Doha with more than vague promises and hot air. In the meantime, it is through initiatives like Plant a Pledge that we can effect change.
Bianca Jagger is Founder and Chair, Bianca Jagger Human Rights Foundation, a Council of Europe Goodwill Ambassador and a Plant a Pledge Campaign Ambassador. She tweets @biancajagger