Author Archives: Ilissa Ocko

Climate hope amid melting ice, rising temps

(This post originally appeared on EDF Voices)

An ice berg drifts off a West Antarctica glacier — Courtesy NASA

 

As 2014 draws to a close, two recent developments show that global temperatures are rising at an alarming rate. The world, it seems, is on a run-away train – and yet, we have more reason to feel hopeful than we did a year ago.

I’ll explain why that is. But first, let’s have a look at where we are right now.

West Antarctica ice sheet loss is accelerating

The latest science shows that ice loss from West Antarctica has been increasing nearly three times faster in the past decade than during the previous one – and much quicker than scientists predicted.

This unprecedented ice loss is found to be occurring because warm ocean water is rising from below and melting the base of the glaciers, dumping huge volumes of additional water – the equivalent of a Mount Everest every two years – into the ocean.

If we lost the entire West Antarctic ice sheet, global sea level would rise 11 feet, threatening nearly 13 million people worldwide and affecting more than $2 trillion worth of property.

2014 may be warmest year on record

The World Meteorological Organization announced recently that 2014 is on track to be one of the hottest – if not the hottest – year on record.

Continued emissions of heat-trapping gases from energy use, land use, industry, and waste activities contribute to these rising global temperatures.

But there's hope

At Environmental Defense Fund, we spent a year talking to experts from academia, industry, and the activist community to understand what needs and can be done to address climate change.

We analyzed the scientific, economic and political landscapes, and we see that it's possible to reverse the relentless rise of global greenhouse gas emissions within the next five years. But only if countries devote sufficient attention to the task.

What may surprise you is that this can be done with current technology, and at a reasonable cost.

There are two critical components of such a strategy.

One: A few countries can make big progress.

China, the United States, and Europe account for more than half of all global emissions of carbon dioxide from energy use.

Improving energy efficiency, employing carbon markets, enacting power plant standards, and accelerating clean energy deployment are all part of our five-year strategy to curb emissions.

The European Union already has an emission reduction plan in place, the U.S. is taking action on carbon pollution from cars and power plants, and China recently reached a historic agreement with the United States to limit emissions.

Two: By reducing short-lived climate pollutants we'll come a long way.

If we cut emissions of short-lived pollutants such as methane, which only last in the atmosphere for at most a couple of decades, we can take a sizeable bite out of warming in the near-term.

Methane contributes to around a quarter of the warming we are experiencing today, so this is an enormous opportunity we cannot pass up.

We already have the technology in hand to reduce methane emissions from the oil and gas industry in a cost-effective way. Industry would spend just a penny more for each thousand cubic feet of gas it produces.

It’s not too late

While turning the corner on global emissions by 2020 is feasible, it can only happen with many partners working together.

EDF expects to take actions in alliance with many others that contribute to about half of the needed reductions in short-lived and long-lived emissions we've identified in our five-year strategy. We're also working to set the stage for actions post-2020 that will drive down emissions even further.

While some of the climate change consequences may be irreversible – as appears to be the case with West Antarctica – we can still set ourselves on a much better path for the future by taking action now.

Posted in Arctic & Antarctic, Greenhouse Gas Emissions, News, Science| Comments closed

An Urgent Call to Climate Action in the IPCC Synthesis Report

Photo: IPCC

It was released two days late for Halloween, but an international report on the dangers of climate change still has plenty of information about our warming planet that will chill you to the core.

The report is the latest from the Intergovernmental Panel on Climate Change (IPCC).

The IPCC releases a series of reports every six or seven years that assess the latest data and research on climate change. This latest is the Fifth Assessment Synthesis Report—a culmination of three earlier reports in this series.

The Synthesis Report summarizes the physical science of climate change; current and future impacts, vulnerabilities, and adaptation of the human and natural worlds; and mitigation opportunities and necessities.

More than anything else, the report underscores the urgent need for action.

Here are 13 details from the report that illustrate why:

1.  “Warming of the climate is unequivocal… The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, and sea level has risen.”

2.  Changes in climate have impacted all continents and the oceans.

3. The period from 1983 to 2012 was likely the warmest 30-year period of the last 1400 years in the Northern Hemisphere.
Glaciers have continued to shrink almost worldwide. Northern Hemisphere spring snow cover has continued to decrease.

4. Permafrost temperatures have increased in most regions since the early 1980s. Arctic sea-ice has decreased in every season and in every successive decade since 1979.

5. From 1901 to 2010, global mean sea level rose by more than half a foot. The rate of sea-level rise since the mid-19th century has been larger than the mean rate during the previous two millennia.

6. In the future, it is virtually certain that there will be more frequent hot and fewer cold temperature extremes in most areas, on both daily and seasonal timescales. It is very likely that heat waves will occur more often and last longer. The oceans will continue to warm and acidify, and global mean sea level to rise.

7. A large fraction of species face increased extinction risk due to climate change during and beyond the 21st century. Most plant species cannot naturally shift their geographical ranges sufficiently fast to keep up with climate change.

8. Climate change puts humanity at risk from heat stress, storms and extreme precipitation, inland and coastal flooding, landslides, air pollution, drought, water scarcity, sea-level rise, and storm surges. Climate change is projected to undermine food security.

9. “Human influence on the climate system is clear.” Atmospheric concentrations of carbon dioxide, methane and nitrous oxide are unprecedented in at least the last 800,000 years.

10. Continued emission of greenhouse gases will cause further warming and long-lasting changes in all components of the climate system, increasing the likelihood of severe, pervasive and irreversible impacts for people and ecosystems.

11. It is virtually certain that global mean sea-level rise will continue for many centuries beyond 2100, with the amount of rise dependent on future emissions.

12. Many adaptation and mitigation options can help address climate change, but no single option is sufficient by itself. Adaptation can reduce the risks of climate change impacts, but there are limits to its effectiveness.

13. Substantial emissions reductions of greenhouse gases – including carbon dioxide and methane — over the next few decades can reduce climate risks in the 21st century and beyond, increase prospects for effective adaptation, reduce the costs and challenges of mitigation in the longer term, and contribute to climate-resilient pathways for sustainable development.

According to the IPCC Synthesis Report, planet Earth is in pretty dire shape – but the report isn’t hopeless.

Imagine our planet as a patient at a doctor’s office. It’s too late to just stay healthy – we’ve already caught a cold. But we can prevent the cold from deteriorating into pneumonia.

In order to do that, though, we need to act now. We need people, and governments, across the world to join together to reduce greenhouse gas emissions, support adaptation efforts, and help reduce the damages from climate change.

Posted in Basic Science of Global Warming, Extreme Weather, Greenhouse Gas Emissions, International, News, Policy, Science| Comments closed

How scientists linked the California drought to climate change

A drought-stricken vineyard in Napa Valley. Source: John Weiss/Flickr

California has officially entered its fourth consecutive year of drought, and is trapped in its worst water shortage situation ever.

Because we know that human-caused climate change cantrigger and exacerbate drought conditions, media, public officials, California residents and scientists have all been wondering for years if rising global temperatures likely caused or contributed to the current drought in California.

The short answer: Yes, they did.

Weather won’t cooperate

Scientists have suspected for some time now that a certain meteorological condition lies behind the long-lasting California drought. The persistence of a stubborn high-pressure system off the coast has been preventing storm systems from reaching California and instead deflecting them to Alaska and elsewhere.

While weather events are almost always multi-causal, the California drought is largely a result of this atmospheric weather pattern. The question is whether climate change has influenced the development, or sustenance, of this system.

Stanford scientists connected the dots

When destructive events happen, people want to know right then and there what’s going on— whether it’s an epidemic, riot or weather disaster.

But evaluating an extreme weather event for climate change influences is a scientific process that takes several months of computer simulations and statistical techniques. It can frustrate some who demand an answer right away.

Well, the results from several, month-long studies are finally in. Scientists from Stanford have found that the meteorological conditions that have caused the California drought are far more likely to occur in today’s warming world than in one without human-caused emissions of greenhouse gases.

It shows us – ironically and tragically – that the state thatleads the nation in curbing greenhouse gas emissions is right now suffering more than any other from climate change.

California is not alone

The California drought attribution studies are a subset of alarger collection of recently published studies that explain 16 extreme weather and climate events of 2013.

Twenty research teams explored the causes of events such as heat waves in Australia, New Zealand, Korea, Japan, China, and Europe; torrential downpours in Colorado and India, a blizzard in South Dakota, and a cold spell in the United Kingdom.

The studies overwhelmingly indicated that all heat waves were largely attributable to human-caused climate change. One study even suggested that the heat wave in Korea has been made 10 times more likely due to human influence.

The extreme rainfall events in India were concluded to have been more likely in a human-influenced world, but data for assessing precipitation events is rather limited as compared to heat waves. Further, studies concluded that the extreme rainfall event in Colorado, the blizzard in South Dakota, and the cold spell in the U.K. were unlikely to have been influenced by climate change.

Climate change is happening. Now.

So for anyone who may still think that the consequences of climate change are in the distant future, this collection of studies suggest that human-caused climate change is right now causing a crisis in America’s most populous state and the world’s eighth largest economy.

California reminds us that climate change is a major concern for societies everywhere, and that all nations are vulnerable to extreme weather events. It’s time we roll up our sleeves and stop this, once and for all.

This blog originally appeared on EDF Voices 

Posted in Basic Science of Global Warming| Comments closed

Why California thirsts for rain and the East Coast gets soaked

Source: Flickr/Jared Tarbell

If you think the weather’s acting strange, you’re correct. Extreme weather in the United States is trending upward, and human-caused climate change has already been blamed for much of it – most recently in connection with theCalifornia drought.

But along with extreme weather we’re also getting extreme contrasts. What on Earth is going on when New York gets endless rain and San Francisco none, and when one part of the country is freezing while another suffers under record heat?

You guessed it, rising temperatures have something to do with it – and here’s how.

Rain patterns are changing

In the Northeast, the combination of more moisture in the atmosphere from a warmer world and changes in circulation patterns are bringing more rain. In the Southwest, meanwhile, rainfall is suppressed by a northward expansion of high pressure in the subtropics.

The crippling drought now plaguing California is due to a persistent high pressure system off of the coast that is deflecting storms away from the region. A recent study shows that these systems are much more likely to occur with human-caused climate change.

Rain is more intense

Heavy downpours are controlled by cloud mechanisms and moisture content, which are both changing as global temperatures rise. Clouds that can dump a lot of rain are more common in a warmer atmosphere.

More evaporation has led to more moisture in the atmosphere which, in turn, leads to more intense rainfall when it rains. That helps explain why the entire U.S. is experiencing more heavy downpours – even in the drought-stricken West.

Droughts are taking hold

Rain and evaporation will determine how moist the soil will be. So although evaporation is increasing nationwide due to warmer temperatures, higher precipitation in the Northeast yields a net increase in soil moisture in that part of the country.

In the Southwest, on the other hand, the drop in overall precipitation brings drier conditions that spawn or magnify drought. As the soil there dries out, the incoming sunlight will heat the ground instead of evaporating water from the soil. This creates a vicious cycle of more heat and less rain.

Flooding is more common

The potential for flooding, meanwhile, depends a lot on what's going on with the soil. The higher the soil moisture content, the higher the chance that there will be more runoff from rainfall.

Because soil moisture is increasing in the Northeast, flooding events are on the rise. Fortunately for the region, many heavy rain storms occur in the summer and fall when soil moisture is low and the ground can absorb more water.

On the other hand, the sea level has risen by a foot since the 1900s in the Northeast. That, in turn, contributes to more flooding.

Disaster costs are also rising – but there is hope

In 2013, intense storms, severe regional drought, and extreme flooding led to more than $9 billion in disaster costs in the U.S. alone. It’s uncertain what the total bill was if you factor in ongoing agriculture, human health and infrastructure losses from changing weather conditions

Unless we curb emissions of heat-trapping gases, scientists expect these trends to continue and worsen – and the contrast between wet and dry areas of the U.S. will likely become even sharper. Our hope now is that the push for climate action amps up so we can finally set ourselves on a better path for the future.

This post originally appeared on EDF Voices 

Posted in Basic Science of Global Warming, Greenhouse Gas Emissions, Science| Comments closed

Study: Climate change may push hurricanes farther north, south

A satellite image of Irene, a Category 1 hurricane, as it made landfall in North Carolina in August of 2011. Source: NASA/NOAA GOES project

The hurricane season of 2014 just kicked off, and with two devastating storms wreaking havoc along the northeastern United States coast over the last few years, it’s no wonder everyone’s on edge.

We’re concerned about hurricanes becoming more frequent and intense, and about the worsening storm surge caused by a rise in sea levels. But flying under the radar is a fourth link between hurricanes and climate change: how climate change affects the location of hurricanes.

new study led by researchers at the National Oceanic and Atmospheric Administration, the Massachusetts Institute of Technology and Princeton University found that hurricanes have been shifting pole-ward at a rate of 30 to 40 miles per decade over the last 30 years.

It means they are moving closer to major population centers such as Washington, New York and Boston.

The likely cause? Human-caused climate change.

The migration of hurricanes has “potentially profound consequences for life and property,” the authors of the study warn in an article published recently in the journal Nature.

Increasing hazard exposure and mortality risk from tropical cyclones may be compounded in coastal cities outside the tropics, while being offset at lower latitudes.”  

Linking climate change to hurricane location

This finding is an important advancement in scientists’ understanding of how climate change has already contributed to extreme weather events. Research shows that the rise in global temperatures already causes more warm days, heat waves, and heavy rainfall.

Detecting trends in hurricane activity has been difficult, however, due to inconsistent and often unreliable historical data.

To get around this data challenge, the scientists at NOAA, MIT and Princeton developed a new technique that relies on a dependable subset of the data, and which teases out natural events such as El Niño to detect a distinct relationship between hurricane activity and climate change.

Their conclusion: Hurricanes are drifting toward the poles most likely due to an expansion of the Hadley Cell, a permanent atmospheric circulation feature that carries heat from the tropics to the Earth’s temperate zones.

Scientific understanding is that the Hadley Cell expansion is a result of the increase in heat-trapping gases in the atmosphere from human activities. So as we continue to drive cars, generate electricity at fossil-fueled power plants, cut down trees, and farm – we are indirectly pushing hurricanes farther north and south.

The new study is groundbreaking not only because it uses a novel technique, but also because it links a hurricane trend to climate change.

What we know so far

So where are we today with hurricanes and climate change?

Scientists studying hurricanes:

  • Have found no observed trend in frequency
  • Have not been able to detect trends in intensity  and duration
  • Are confident that human-caused sea level rise is contributing to storm surge
  • Expect the frequency of intense storms to increase in the future
  • Have now detected a robust trend in location shifts that is likely due to human activity

This new research presented in Nature suggests that hurricanes are migrating toward the poles and may devastate densely populated coastal regions that had previously, for the most part, been spared such storms.

It’s yet another reason why we must act now to curb carbon pollution and limit climate change.

This post first appeared on EDF Voices

Posted in Basic Science of Global Warming, Clean Power Plan, Extreme Weather, Greenhouse Gas Emissions| Comments closed

New report: How climate change is impacting where you live

The National Climate Assessment (NCA) report, prepared by the U.S. Global Change Research Program, is essentially the U.S. equivalent of the Intergovernmental Panel on Climate Change (IPCC): Using the best available science, over 300 experts synthesized current understanding of observed and future climate changes and impacts, particularly in the U.S. The third ever NCA was released today, and concludes beyond a reasonable scientific doubt that Americans are being affected by climate change.

Among the findings:

  • U.S. average temperatures have increased by 1.3 to 1.9ºF since record-keeping began in 1895, and most of this warming has occurred since 1970
  • Heavy precipitation has increased in many parts of the country
  • Extremes such as heat waves, droughts, floods, and North Atlantic hurricanes are more frequent and/or intense
  • Summer sea ice in the Arctic has halved since record-keeping began in 1979
  • Sea level rise has increased coastal erosion and storm surge damage

These changing conditions produce a variety of tangible stresses on society by affecting human health, water resources, agriculture, energy, infrastructure, and natural ecosystems. The particular impacts vary by region, but no corner of the country is immune to the change.

So what’s happening where you live?

Source: National Climate Assessment

Unless we take immediate action to curb our emissions of heat-trapping gases, the foreseeable future will be plagued by further warming and worsening impacts. The good news is that because we know what the cause is, we also know what is needed in order to stabilize our planet. We must come together now—locally, nationally, and internationally—and work towards a better future.

This post first appeared on our EDF Voices blog

Posted in Arctic & Antarctic, Basic Science of Global Warming, Extreme Weather, Oceans, Science| Comments closed
  • About this blog

    Expert to expert commentary on the science, law and economics of climate change.

  • Categories

  • Get blog posts by email

    Subscribe via RSS

  • Meet The Bloggers

    Megan CeronskyMegan Ceronsky
    Attorney

    Nat KeohaneNat Keohane
    Vice President for International Climate

    Ilissa Ocko
    High Meadows Fellow, Office of Chief Scientist

    Peter Zalzal
    Staff Attorney

    Gernot Wagner
    Senior Economist

    Graham McCahan
    Attorney

    Mandy Warner
    Climate & Air Policy Specialist

    Pamela Campos
    Attorney

    Kritee
    High Meadows Scientist