Climate change: what are world leaders waiting for?

The effects of climate change can already be seen in extreme weather events across the world, says Bianca Jagger. Here's how to make your contribution to the fight against it.

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

The effects of climate change can already be seen in extreme weather events. Photograph: Getty Images
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Inside Big Ben: why the world’s most famous clock will soon lose its bong

Every now and then, even the most famous of clocks need a bit of care.

London is soon going to lose one of its most familiar sounds when the world-famous Big Ben falls silent for repairs. The “bonging” chimes that have marked the passing of time for Londoners since 1859 will fall silent for months beginning in 2017 as part of a three-year £29m conservation project.

Of course, “Big Ben” is the nickname of the Great Bell and the bell itself is not in bad shape – even though it does have a huge crack in it.

The bell weighs nearly 14 tonnes and it cracked in 1859 when it was first bonged with a hammer that was way too heavy.

The crack was never repaired. Instead the bell was rotated one eighth of a turn and a lighter (200kg) hammer was installed. The cracked bell has a characteristic sound which we have all grown to love.

Big Ben strikes. UK Parliament.

Instead, it is the Elizabeth Tower (1859) and the clock mechanism (1854), designed by Denison and Airy, that need attention.

Any building or machine needs regular maintenance – we paint our doors and windows when they need it and we repair or replace our cars quite routinely. It is convenient to choose a day when we’re out of the house to paint the doors, or when we don’t need the car to repair the brakes. But a clock just doesn’t stop – especially not a clock as iconic as the Great Clock at the Palace of Westminster.

Repairs to the tower are long overdue. There is corrosion damage to the cast iron roof and to the belfry structure which keeps the bells in place. There is water damage to the masonry and condensation problems will be addressed, too. There are plumbing and electrical works to be done for a lift to be installed in one of the ventilation shafts, toilet facilities and the fitting of low-energy lighting.

Marvel of engineering

The clock mechanism itself is remarkable. In its 162-year history it has only had one major breakdown. In 1976 the speed regulator for the chimes broke and the mechanism sped up to destruction. The resulting damage took months to repair.

The weights that drive the clock are, like the bells and hammers, unimaginably huge. The “drive train” that keeps the pendulum swinging and that turns the hands is driven by a weight of about 100kg. Two other weights that ring the bells are each over a tonne. If any of these weights falls out of control (as in the 1976 incident), they could do a lot of damage.

The pendulum suspension spring is especially critical because it holds up the huge pendulum bob which weighs 321kg. The swinging pendulum releases the “escapement” every two seconds which then turns the hands on the clock’s four faces. If you look very closely, you will see that the minute hand doesn’t move smoothly but it sits still most of the time, only moving on each tick by 1.5cm.

The pendulum swings back and forth 21,600 times a day. That’s nearly 8m times a year, bending the pendulum spring. Like any metal, it has the potential to suffer from fatigue. The pendulum needs to be lifted out of the clock so that the spring can be closely inspected.

The clock derives its remarkable accuracy in part from the temperature compensation which is built into the construction of the pendulum. This was yet another of John Harrison’s genius ideas (you probably know him from longitude fame). He came up with the solution of using metals of differing temperature expansion coefficient so that the pendulum doesn’t change in length as the temperature changes with the seasons.

In the Westminster clock, the pendulum shaft is made of concentric tubes of steel and zinc. A similar construction is described for the clock in Trinity College Cambridge and near perfect temperature compensation can be achieved. But zinc is a ductile metal and the tube deforms with time under the heavy load of the 321kg pendulum bob. This “creeping” will cause the temperature compensation to jam up and become less effective.

So stopping the clock will also be a good opportunity to dismantle the pendulum completely and to check that the zinc tube is sliding freely. This in itself is a few days' work.

What makes it tick

But the truly clever bit of this clock is the escapement. All clocks have one - it’s what makes the clock tick, quite literally. Denison developed his new gravity escapement especially for the Westminster clock. It decouples the driving force of the falling weight from the periodic force that maintains the motion of the pendulum. To this day, the best tower clocks in England use the gravity escapement leading to remarkable accuracy – better even than that of your quartz crystal wrist watch.

In Denison’s gravity escapement, the “tick” is the impact of the “legs” of the escapement colliding with hardened steel seats. Each collision causes microscopic damage which, accumulated over millions of collisions per year, causes wear and tear affecting the accuracy of the clock. It is impossible to inspect the escapement without stopping the clock. Part of the maintenance proposed during this stoppage is a thorough overhaul of the escapement and the other workings of the clock.

The Westminster clock is a remarkable icon for London and for England. For more than 150 years it has reminded us of each hour, tirelessly. That’s what I love about clocks – they seem to carry on without a fuss. But every now and then even the most famous of clocks need a bit of care. After this period of pampering, “Big Ben” ought to be set for another 100 or so years of trouble-free running.

The Conversation

Hugh Hunt is a Reader in Engineering Dynamics and Vibration at the University of Cambridge.

This article was originally published on The Conversation. Read the original article.