A strongly-worded report by the UN Intergovernmental Panel on Climate Change (IPCC) and a vaguely worded "weak intentions" of nations encapsulate the state of the global climate and state of [in]action to mitigate disastrous effects.
While the year saw continuing observations of ice melting rapidly at the poles, typhoons battering island nations and devastating floods, the second half saw the hottest months on record as reported by the US National Oceanic and Atmospheric Administration.
With global land and ocean average surface temperatures 0.68C above the 20th century average, the period between 1983 and 2012 was the warmest 30-year period in 1,400 years.
In just two decades, 50% of summers across the globe could be 'extreme' events like the one in 2013, warned experts. Man-made climate change has contributed to a 60-fold increase in the likelihood of extreme temperatures since the early 1950s.
The second-largest body of ice on Earth, the Greenland ice sheet alone shed about 243 gigatonnes of ice per year from 2003-09.
The discovery of 500 methane vents on the Atlantic ocean floor, off the US coast, has set off alarm signals that many more vents, almost 30,000 elsewhere could end up releasing more carbon into the air.
The last four decades have seen almost four million tonnes of methane released from hydrate decomposition off the US coast alone, brought along by warming waters.
The evidence of a warming world has been piling up.
Carbon dioxide emissions responsible for global warming continued to increase though the rate of increase showed a drop.
Global carbon emissions stood at 35 billion tonnes in 2013, a record so far. Fossil fuel use and cement production contributed majorly. The world is on track to pile 40 billion tonnes of carbon emissions this year.
China, the USA and the EU remain top emitters of CO2, accounting for 29%, 15% and 11% respectively of the world's total emissions.
A third of the global emissions arise from the energy sector.
Deforestation rates of 29% in the Amazon in the period between 2012-2013 aggravated the carbon problem. Cutting down tropical rainforests not only increases carbon dioxide in the air but also affects rainfall patterns and raises temperatures across the globe.
The IPCC's Fifth Assessment Report released in April, and brought out jointly with the efforts of more than 1,271 researchers, concluded that unless fossil fuels are phased out, the rise in temperature could be as much as 5C by 2100.
Any rise above 2C will set off irreversible climate change.
Net global emissions of carbon must drop 40-70% by 2050, hitting zero by the end of the century, said the report.
This will mean limiting carbon dioxide levels in the atmosphere to 450 parts per million (ppm) by 2100. At present it hovers around 400 ppm.
But, the world is already locked into an unavoidable rise in temperature of almost 1.5C thanks to past and predicted emissions.
This can rise up to 2C by mid-century and 4C by end of the century if there are no concerted actions to curb emissions, said a World Bank sponsored report titled Turn down the heat.
A UNEP report has also called for a complete halt to emissions by the end of the century.
Touching on the finite carbon budget, the UNEP had pointed out that there was less than 1000 gigatonnes of carbon dioxide left for the world to emit if it is to avoid irreversible climate change.
How will this be shared? That has been the bone of contention between the developed and developing worlds.
The international pact on climate change which expired in 2012, Kyoto Protocol is hoped to be replaced by an ambitious deal to be signed in Paris next year. It will set the path for nations post-2020.
The UN meet at Lima was meant to lay down a few common points of agreement before Paris. But after days of tussles between the rich and poor blocs, Lima barely managed to cobble up a diluted action plan.
The Lima Call For Climate Action does nothing to halt the world from its present trend towards a 3-4C temperature rise and merely puts off tough decision to the end of next year.
It merely seeks an "ambitious agreement" in 2015 urging nations to set targets beyond current undertaking and reflecting "differentiated responsibilities and respective capabilities" of each nation; it asks developed countries to provide financial support to "vulnerable" developing nations; and seeks submission of national pledges by the first quarter of 2015 by willing states.
That nations beyond a couple of them have hardly delivered on previous promises is evident in the green climate fund which was to provide $100bn annually by 2020, but hardly has managed $10bn so far.
With the Lima plan merely calling on voluntary actions, adaptation costs of climate change will place a burden on poor nations.
Financial support to the tune of £64-£96bn ($100bn-150bn) every year by 2030 could achieve efficiency and cover the total investments in low carbon technologies needed in developing countries to keep within the 2C temperature rise target, said a Potsdam Institute for Climate Impact Research study.
World electricity generation is forecast to grow by 67% from 22,126 terawatt-hour (TWh) in 2011 to 37,000 in 2030. A major part of this additional capacity is expected to be based on fossil fuels.
Transforming the global energy industry is possible and affordable-at a cost of about 0.06% of global consumption growth per year, said IPCC experts.
While renewable power capacity has grown 85% over the past 10 years, reaching 1,700 GW in 2013, renewables constitute only 30% of all installed power capacity.
International Renewable Energy Agency also said that a doubling in the share of renewables could reduce the global average emissions and coupled with greater energy efficiency keep atmospheric CO2 below 450 ppm.
A further 40% reduction in emissions can be got by shift to public transport by 2050 said the Institute for Transportation and Development Policy (ITDP) and University of California, Davis.
What nations are doing
Germany plans to shut down eight additional coal-fired plants besides the 50 announced earlier, to cut its emissions by 40% until 2020.
But UK trails with the Committee on Climate Change (CCC) saying the country will not be able to meet its targets of reducing emissions to 80% below 1990 levels by 2050.
Trends indicate emissions will double.
The EU announced plans to cut emissions to 40% below 1990 levels by 2030 while the US will strive to go as much as 28 percent below 2005 levels in the same period which does not measure up to half the EU committment.
China agreed to peak its emissions by 2030 and there is no saying what the peak will be.
Rapid industrialisation in China has led to a 45% increase in its overall energy consumption between 2008 and 2013, most of it generated using coal.
Actions at the level of companies and organisations have been positive. But whether those will be enough to keep the temperature reigned in will have to be seen. Hopefully, it wont need catastrophes to spur the nations into action that goes beyond mere promises.