The world is finally coming to terms with an inconvenient truth.

Across the globe, leaders are waking up to the fact that global warming is a real threat. And its impact is palpable, often immediate—disasters and human suffering carried live on television or the Internet almost as they occur.

Last month, as the United States prepared for Christmas, its East Coast was buried under the avalanche of gale-force blizzards. This record snowfall was a reprise of a wintry assault that devastated major cities in the mid-Atlantic region in February last year.

In July last year, an intense heat wave spread from Maine to Pennsylvania. By the following month, the continuing drought shrank Lake Mead, America’s largest reservoir in Nevada and Arizona, by a significant margin.

Then in spring, torrential rains unleashed floods across southeast America even as summer heat waves ravaged much of the northern hemisphere.

As 2011 approached, thousands in Queensland, Australia, suddenly found themselves marooned by floodwaters of Tropical Cyclone “Tasha,” which eventually swamped a vast land area equivalent to France and Germany combined.

While diplomats and scientists pondered over an accord that could replace the Kyoto Protocol, 19 nations were experiencing unusually high temperatures, including 53.5 degrees Celsius in Pakistan, the hottest ever in Asia. In Pakistan, record monsoon rains destroyed infrastructure, left thousands dead and millions homeless.

In Eastern Europe, Russia suffered its hottest year in 1,000 years of history. At least 10,000 people died from Moscow’s heat phenomenon. Wildfires erupted across the country, heavily damaging its wheat crop and forcing Moscow to impose an export ban that raised global wheat prices.

Here at home, in Baguio City, millions worth of fruits and vegetables were ruined by heavy frost of an unseasonably cold weather. More than a week of abnormally heavy rains left 33 dead last December. About 70,000 fled the flash floods and landslides in Davao del Norte, Compostela Valley and Albay.

Our people in those areas remain in turmoil—hundreds of hectares of rice lands, private property and infrastructure destroyed; a total of P431 million in newly planted crops and fertilized soil washed away; and contagious diseases and rat hordes added to their immense misery.

This swath of destruction and distress foretell more frequent weather extremes common to most global simulations of future climate. This means that 2010 could have marked the early stages of a longer trend and far more volatile weather patterns all over the world.

Scientists are beginning to detect the climate system’s instability as a result of its changing chemical composition, increasing heat and water vapor in the atmosphere, and altered air and ocean currents prompted by the loss of Arctic sea ice.

Greenhouse gas

This instability, of course, is mainly the consequence of global warming brought about by excessive greenhouse gas emissions. Most of these emissions come from burning fossil fuels—coal, oil and natural gas—to produce energy from deforestation and from agricultural activity.

The Earth heats up when greenhouse gases (carbon dioxide, water vapor, nitrous oxide and methane) trap heat and light from the sun in the atmosphere. This increases the global temperature, triggering changes in weather patterns.

The year 2010 vied with 1998 as the hottest year in a 32-year satellite-recorded span, according to John Christy, a professor of atmosphere science and director of the Earth System Science Center at the University of Alabama.

Significantly, both 1998 and 2010 were years in which El Niño—a Pacific Ocean warming phenomenon—raised global temperatures. In recent months, a La Niña event, the cooling of the Pacific Ocean, has been building up, inducing cooler temperatures in tropical regions during the final quarter of 2010 and bringing heavy rains.

These weather anomalies are under intense scrutiny. As part of an ongoing project between University of Alabama, the National Oceanic and Atmospheric Administration and NASA, Christy and an associate, Roy Spencer, employ data from advanced microwave sounding units and satellites to get accurate readings for all regions of the planet, including remote deserts, oceans and rainforests.

Satellite instruments now measure atmospheric temperature from the Earth’s surface up to an altitude of 8 kilometers, according to John Topping, president of the Washington-based Climate Institute, the oldest nongovernment organization that pioneered in addressing climate change issues.

Planet continues to warm

Their collective findings: The planet continues to warm unevenly as you go up north. The Arctic Ocean has heated 1.66 degrees Celsius in the past 32 years while Antarctica cooled by about 0.29 degrees Celsius. As a result, the Arctic’s contiguous continent, including Canada and the United States, has warmed by about 0.67 degrees Celsius since 1979.

These findings explain why the 2010 coral bleaching had worsened from the time of the super El Niño of 1988; why the Arctic Ocean was declared ice-free last summer for the first time in eons; and why the pine tree beetle epidemic in Yellowstone, which decimated the national park’s pine forests, had begun its journey to Canada’s boreal forest in Alberta.

Preventing the Cassandra forecast in climate change calls for behavioral change on small and grand scales. For instance, the annual explosion of fireworks that mimic greenhouse gas emissions.

As a senator from 1986 to 1998, and every year thereafter, I have consistently voiced dismay over the general disregard for the adverse environmental, safety and health impact of massive firecracker carnivals during New Year celebrations.

As environment secretary in 2001, we recorded a 2,000 percent increase in Metro Manila’s carbon and nitrogen dioxide emissions as a result of massive firecracker explosions. With at least 50 percent of the nation’s 90 million people living in urban areas, I would not be surprised if there was another 2,000-percent increase in greenhouse gas emissions during the recent New Year.

Deep, early cuts

We can do more by embracing the principle of “deep and early emissions cut” for developed countries. This notion, which we advocated as early as 2008 in Poznan, Poland, was affirmed last year by President Benigno Aquino III at the UN General Assembly in New York City.

The principle’s urgency lies in the importance of keeping the global heating below 2 degrees Celsius. Unfortunately, the December 2010 climate conference in Cancun, Mexico, eluded this notion of deep and early cuts. The likely result will be a huge, five-gigaton gap of greenhouse gas emissions in the commitments of developed nations, a gap that will surely allow the terrifying prospect of up to 4 degrees Celsius global warming by 2050.

There exists sufficient scientific data, expertise and experience for world leaders to forge a climate treaty replacing the Kyoto Protocol. We only need a spirited consensus to stop a global slide toward the tipping point—the irreversible threshold of doom that scientists predict.

UN Secretary General Ban Ki-moon’s appeal cannot be more emphatic: “We must harness the necessary political will to seal the deal on an ambitious new climate agreement … If we get it wrong we face catastrophic damage to people, to the planet.”

Our overwhelming hope is that this year’s climate meeting in Johannesburg, South Africa, will be a crucial turning point in humanity’s quest to minimize global warming. But clearly, we must rise above narrow national agendas.

For millenniums, we have exploited nature’s bounty and, in the process, despoiled our own habitat. Now, world leaders must summon mankind’s great genius and nobility to preserve this planet and our species.

(Editor’s Note: Heherson T. Alvarez is a member of the Climate Change Commission, chaired by President Aquino. A two-term senator, he chaired the Senate committee on environment for 10 years. In 1996, he organized the First Asia-Pacific Conference on Climate Change in Manila. For his pioneering environmental leadership, he received the Outstanding Public Policy Award from the Climate Institute, the first non-Western recipient.)