Selected category: Extreme Weather

Hurricane Matthew And Climate Change: What We Know So Far

Image source: NASA

Hurricane Matthew. Image source: NASA

As I write this, Hurricane Matthew is battering the Atlantic coast of Florida, having wreaked havoc on Haiti and the Bahamas. In Haiti hundreds lost their lives due to the Hurricane’s destructive winds and storm surge.

With half a million Floridians already without power even before Matthew makes landfall, there is sure to be significant damage in Florida and other portions of the southeast U.S. from this Category 3 storm, the first major hurricane to strike the U.S. since Wilma in 2005. Our first and highest priority is to help the victims and others in the path of the storm.

However, as with any destructive weather event, people are asking about the role of climate change.

We know that increases in sea level caused by climate change result in higher and more destructive storm surges, like the one that swamped lower Manhattan during Superstorm Sandy in 2012. Coastal towns suffer greater damage because the ocean starts out higher, and the storm shoves more water inland. Coastal states like South Carolina and Florida – and the rest of us through taxes and insurance rates – will pay billions as a result.

But what about the connection between climate change and the strength of hurricanes themselves?

Hurricanes are fueled by the warm waters of the tropical oceans, which have been warming as the result of increased emissions of greenhouse gases.

However, hurricanes are also impacted by wind shear – the change of wind speed and direction with height. For a hurricane to grow and strengthen it needs a low wind shear environment, and some research indicates that climate change may actually increase wind shear over the tropical Atlantic. And that’s the rub. When it comes to climate change and hurricanes, the warming oceans and increasing wind shear are in competition. Science is still working out which mechanism will dominate as the global climate continues to warm – so stay tuned.

But there is more to the story than just the relationship between the intensity or frequency of hurricane and global warming. Because the climate system is so complex, no storm happens in a vacuum. Scientists have been working on the issue of “attribution”— How much can we know about the link between specific storms and climate change? The organization Climate Central has also been working intensively in this area.

While we await attribution studies, we shouldn’t lose site of the bigger picture: we already know that climate change is doing tremendous damage to our environment and our economy. Citibank estimates the cost of inaction on climate change is in the trillions. So let’s first help those hurt by this storm, then focus on cutting the pollution that is causing so much damage to our world.

Also posted in Basic Science of Global Warming, Greenhouse Gas Emissions, Oceans, Science| Comments are closed

The Impacts of Climate Change on Human Health – a Sobering New Report

We have even more information this week about the ways climate change poses a threat to human health.

The U.S. Global Change Research Program just released its newest report—The Impacts of Climate Change on Human Health in the United States. This scientific assessment is the culmination of three years of work by hundreds of experts, and builds on the more general National Climate Assessment released in 2014.

The report concludes that every American is vulnerable to the health impacts associated with climate change.

Health Threats from Climate Change graphic

Graphic created by Ilissa Ocko, EDF Scientist

Scientists have known for decades that climate change threatens human health via excessive heat, worsened air quality, water related illnesses, food safety, diseases transmitted by pests like fleas and mosquitos, and mental stress. The new report thoroughly characterizes our current understanding of these impacts.

Because scientific understanding has advanced significantly in recent years, the authors also reviewed new information and insights from several recent scientific, peer-reviewed publications and other publicly available resources.

For example, new data revealed that the Ragweed season has grown by as much as 27 days in the central U.S. from 1995 to 2011, and the incidence of Lyme disease in the Northeast has doubled from 2001 to 2014, both consistent with warming trends.

Recent modeling studies have also improved quantification estimates of and confidence in projected health outcomes from climate change. By midcentury, scientists project that there will be as many as thousands of additional ground-level ozone (smog) related illnesses and premature deaths, and the majority of the western U.S. will have a 500 percent  increase in the number of weeks with risk of very large fires. By the end of the century, scientists project that there will be an additional 27,000 summertime heat-related deaths annually in over 200 U.S. cities (that are currently home to 160 million people), and harmful toxin-producing algal blooms could develop up to two months earlier and persist for up to two months longer.

Through climate and weather changes and disruptions to ecosystems and societal systems, here are the main concerns about climate change impacts on human health:

  • Temperature Related Death and Illness — Future climate warming could cause up to tens of thousands of additional deaths each year from heat in the summer, from loss of ability to control internal temperature, and worsened chronic cardiovascular and respiratory diseases
  • Air Quality Impacts — The future could include limited productivity at work and school due to exacerbated ground-level ozone (smog) health impacts from modified weather patterns conducive to ozone formation, and worsened allergy and asthma conditions from more airborne pollen and longer pollen seasons
  • Vectorborne Disease — The seasonality, distribution, and prevalence of vectorborne diseases, including Lyme disease and West Nile virus,  may change with changing temperature and rainfall patterns due to altered geographic and seasonal distributions of mosquitoes, ticks, and fleas
  • Water-Related Illness — Risk of exposure to illnesses increases as the growth, survival, spread, and toxicity of water-related pathogens and toxins is impacted by temperature and extreme rainfall events, and aging water infrastructure is vulnerable to failure with extreme events and storm surges
  • Food Safety, Nutrition, and Distribution — Rising temperatures, changing weather patterns, and extreme events have consequences for contamination, spoilage, and the disruption of food distribution, whereas higher carbon dioxide levels lower nutritional value of crops despite boosting plant growth
  • Extreme Weather — Fatalities, injuries, and infrastructure damages are imminent with increases in the frequency and/or intensity of extreme precipitation, hurricanes, coastal inundation, drought, and wildfires
  • Mental Health and Well-Being — Mental health conditions may develop with exposure to disasters or worsen by extreme health

Overall, the report is a sobering portrait of the risks we face because of climate change — and it underscores the urgency for climate action.




Also posted in Basic Science of Global Warming, Health, News, Plants & Animals, Science| Comments are closed

Climate Change and Millennials – An Entire Lifetime of Warmer Than Average Temperatures

While reading the announcement that 2015 had broken – indeed, shattered – the hottest year on record set by 2014, there was one fact that really made things personal: we have now had 31 straight years since a single month was cooler than the twentieth century global average temperature. That means that I have never lived through a month that wasn’t warmer than average – never once in my lifetime.

My entire career as a climate scientist is focused on reducing the threat of global warming, and yet I have never even been alive at a time when the climate was stable. I technically don’t even know what normal is.

Warmest Years on Record graphic

So on one hand, you could say that I don’t even know what I am fighting for. On the other hand, I’ve been afforded two unique opportunities because I’ve lived in the shadow of global warming my entire life.

First, because I’ve grown up at a time when heat records are broken over and over again, I was aware of this worldwide crisis during those impressionable and important “pick a major” years of college. I was thus able to set myself on a career path shaped by climate change from the get-go, rather than later on in life once I was already an established professional in something else.

Second, because my elder colleagues have already identified – with extreme confidence – that humans are the main cause of climate change, I’ve been able to focus on solutions from the get-go, and not just causes and impacts. I have thus benefitted from previous scientific research because I could explore avenues to address climate change, because if humans are the cause, then we are also the solution.

And it’s not just me; there is now an entire generation of young people motivated and empowered to do something about climate change. We – almost the entire millennial generation – have never lived in a world without global warming.

Perhaps for similar reasons to mine (and/or because we think we’re special), my generation has shown a propensity for not just caring about climate change, but doing something about it. Whether on their campuses of their schools or the communities where they live, my generation is showing that they want solutions. In fact, eighty-percent of millennials support cleaner energy in the U.S., regardless of party affiliation.

For this reason among others, I am more hopeful about our future than ever before. Climate change has been impacting my generation our whole lives, but it doesn’t have to stay that way. We didn’t ask for this challenge, but I truly believe we’ll be able to rise up to meet it.

Also posted in Basic Science of Global Warming, Greenhouse Gas Emissions, News, Science| Read 1 Response

Urgency and Opportunity for Latino Leadership on Climate

Las Vegas -- Wikimedia Commons

Las Vegas — Wikimedia Commons

When I landed in Las Vegas last week, the weather was a broiling 108 degrees. Ouch.

I braved the Las Vegas heat for one of the most inspiring convenings of Latino leaders in the country, the Annual Conference of the National Association of Latino Elected Officials (NALEO). We had a chance to hear from established and rising Latino leaders, as well as from Presidential candidates, about the challenges facing Latino communities and the many paths forward for creating a brighter future.

What we did not hear about was a vision for places like Las Vegas, where summer temperatures are bound to get hotter and water will become even more scarce in the face of climate change. In fact, there was no formal conversation about what climate change means for the U.S., and specifically for Latinos.

Here’s the short version of the missing conversation on climate: climate change presents challenges to everyone but it is having, and will continue to have, a disproportionate impact on Latinos in the United States.

To illustrate, let’s look at the three states that house more than half the Latinos in the US:

  • California, and the state’s majority Latino population, is facing its fourth year in historic drought that’s been exacerbated by climate change.
  • This summer, Texas experienced unprecedented flooding, nearly canceling out the state’s prior state of drought, in a demonstration of the kind of extreme weather linked to climate change.
  • Florida’s real estate and freshwater is already threatened by initial increases in sea-level rise, which are also eroding the state’s beaches.

There are more than 28 million Latinos facing climate threats in these three states alone. That does not count the millions of other Latinos nationwide who will face extreme heat and longer wildfire seasons in the Southwest this summer. It does not account for all 49 percent of Latinos nationally who live in coastal communities and will face more frequent and intense hurricanes and flooding. It also does not account for the full 14 percent of Latino kids diagnosed with asthma, who will face greater challenges to managing this condition due to more days with unhealthy levels of smog.

That was the bad news. It points to the fact that our leaders should not ignore the impacts of climate change on the Latino community. As climate impacts the air we breathe, threatens water we use for drinking, swimming, farming, and fishing, and even endangers our health, leaders at all levels need to take a proactive stance to protect our communities by addressing climate change.

Here’s the good news — the support is already there to act on climate. National polling has shown that 63 percent of Latinos think the federal government should act broadly to address global warming, while 8 in 10 Latinos want the President to curb the carbon pollution that causes climate change.

There are also some great opportunities hidden among the challenges. For example, today’s clean energy economy is creating more jobs than the fossil fuel economy. Jobs in the clean energy economy also offer higher wages to a wide range of workers, relative to the broader economy.

Which brings me back to Vegas. While there was no formal climate change discussion on the program, Latino environmental leaders from around the country were sparking conversations in the halls about conservation, climate change, and la comunidad. Advocates from New Mexico's Hispanics Enjoying Camping, Hunting, and Outdoors talked with conference guests about the importance of protecting our public lands. Colorado's Nuestro Rio shared their work protecting the Colorado River and our bond to this precious resource.

EDF also played a role, teaming up with GreenLatinos, Green 2.0, and Nuestro Rio to host a reception and highlight the importance of addressing climate change at a national level. Nearly everyone we spoke with about our work was interested in hearing about solutions and how to do more.

As we participated in conference events last week, Pope Francis reminded us that we “have the duty to protect the earth and ensure its fruitfulness for coming generations.” Latino communities, and our leaders, are no exception. We have a duty to address climate change — protecting our families, our children, and our climate is something we cannot afford to gamble on.

Also posted in Clean Power Plan, Greenhouse Gas Emissions, Jobs, News, Partners for Change, Science| Comments are closed

Six Climate Tipping Points: How Worried Should We Be?

One of the biggest fears about climate change is that it may be triggering events that would dramatically alter Earth as we know it.

Known to scientists as “tipping events,” they could contribute to mass extinction of species, dramatic sea level rise, extensive droughts and the transformation of forests into vast grasslands – among other upheavals our stressed world can ill afford.

Here are the top six climate events scientists worry about today.

1. The Arctic sea ice melts

The melting of the Arctic summer ice is considered to be the single greatest threat, and some scientists think we’ve already passed the tipping point.

As sea ice melts and the Arctic warms, dark ocean water is exposed that absorbs more sunlight, thus reinforcing the warming. The transition to an ice-free Arctic summer can occur rapidly – within decades – and this has geopolitical implications, in addition to a whole ecosystem being disrupted.

Photo: Smudge 900)

2. Greenland becomes ice-free

The warming of the Arctic may also render Greenland largely ice-free. While Greenland’s ice loss will likely reach the point of no return within this century, the full transition will take at least a few hundred years.

The impacts of the Greenland ice melt is expected to raise sea levels by up to 20 feet.

Half of the 10 largest cities in the world, including New York City, and one-third of the world’s 30 largest cities are already threatened by this sea level rise. Today, they are home to nearly 1.8 billion people.

Other vulnerable American cities include Miami, Norfolk and Boston.

Photo: siralbertus

3. The West Antarctic ice sheet disintegrates

On the other side of Earth, the West Antarctic ice sheet is also disintegrating. Because the bottom of this glacier is grounded below sea level, it’s vulnerable to rapid break-up, thinning and retreat as warm ocean waters eat away at the ice.

Scientists expect the West Antarctic ice sheet to “tip” this century, and there is evidence that it already began happening in 2014.

However, the entire collapse of the glacier, which would raise sea level by 16 feet, could take a few hundred years.

Photo: BBC World Service

4. El Niño becomes a more permanent climate fixture

The oceans absorb about 90 percent of the extra heat that is being trapped in the Earth system by greenhouse gases. This could affect the ocean dynamics that control El Niño events.

While there are several theories about what could happen in the future, the most likely consequence of ocean heat uptake is that El Niño, a natural climate phenomenon, could become a more permanent part of our climate system.

That would cause extensive drought conditions in Southeast Asia and elsewhere, while some drought-prone areas such as California would get relief.

The transition is expected to be gradual and take around a century to occur – but it could also be triggered sooner.

Photo: Austin Yoder

 5. The Amazon rain forest dies back

Rainfall in the Amazon is threatened by deforestation, a longer dry season, and rising summer temperatures.

At least half of the Amazon rainforest could turn into savannah and grassland, which – once triggered – could happen over just a few decades. This would make it very difficult for the rainforest to reestablish itself and lead to a considerable loss in biodiversity.

However, the reduction of the Amazon ultimately depends on what happens with El Niño, along with future land-use changes from human activities.

Photo: World Bank

 6. Boreal forests are cut in half

Increased water and heat stress are taking a toll on the large forests in Canada, Russia and other parts of the uppermost Northern Hemisphere. So are forest disease and fires.

This could lead to a 50-percent reduction of the boreal forests, and mean they may never be able to recover. Instead, the forest would gradually transition into open woodlands or grasslands over several decades.

This would have a huge impact on the world’s carbon balance because forests can absorb much more carbon than grasslands do. As the forest diminishes, the climate will be affected as will the Earth’s energy balance.

However, the complex interaction between tree physiology, permafrost and fires makes the situation tricky to understand.

Photo: Gord McKenna

Other concerns…

As if that’s not enough, there are a few other tipping events that scientists are also concerned about, but they are even more complex and harder to predict. Examples of such events include the greening of the Sahara and Sahel, the development of an Arctic ozone hole and a chaotic Indian summer monsoon.

How do we keep from tipping over?

We know from measurements that the Earth has had many climate-related tipping events throughout its history. Today’s situation is different, because humans are now driving these changes and the warming is occurring at a faster rate.

But as humans we also have the power to change the trajectory we’re on – possibly in a matter of a few years. We think we know how.

Also posted in Arctic & Antarctic, Basic Science of Global Warming, Greenhouse Gas Emissions, Oceans, Plants & Animals| Read 1 Response

On El Niño, snowballs and real climate science

Source: NASA

Just as we thought science was finally taking root, here comes another article claiming that the rise in global temperatures has nearly stopped over the last 15 years. We heard it most recently from the Wall Street Journal.

Never mind that it’s been 30 years since a month was below the 20th century global average surface temperature. Or that climate change is evidenced by clearly visible sea ice and glacial melt. Skeptics support their argument by pointing out, time and time again, how little the Earth has warmed since 1998.

Indeed, the “nearly-stopped warming” may at face value appear to be supported by convincing scientific data. But don’t be fooled: 1998 was an exceptionally warm year thanks to a very intense El Niño, a naturally-occurring phenomenon involving unusually warm water in the Eastern Pacific Ocean.

The change in temperature from 1998 to today, therefore, is not at all a good representation of the long-term trend. It makes the nearly-stopped warming argument no more scientific than a snowball would be in Washington in February.

Selective statistics don't make a trend

Think of it as if you were to use the holiday season as a benchmark for measuring body weight.

If I looked at the weight change I had between Thanksgiving and December 31, a time of year when I usually enjoy lots of good food, the picture would look very different than if my weight monitoring began the week before Thanksgiving. That's because a Thanksgiving start date would be a higher-than-normal weight day, an anomaly.

And, yet, this is exactly what proponents of the nearly-stopped-warming theory are doing.

While it's true that the rate of temperature change has decreased since 2001, they cherry-pick a recent 15-year period, 1998 to 2012, starting with an initial year that is already way above average to prove their point. Of course, these quasi-scientists aren’t transparent about their strategy, so a non-expert would have to dig into the data to realize they are being tricked.

El Niño always a wild card

El Niño, meanwhile, was just doing what niños tend to do: It threw us for a loop.

The one occurring for 10 consecutive months 1997-98 was the most intense ever recorded, making 1998 the hottest year up until that point. (Three years have since broken that record: 2005, 2010 and 2014.)

Scientists have a number of technical and statistical methods for delineating natural from human influences on the temperature record, and apply these tools depending on the research questions they're trying to answer.

But the overall global record is not touched, so if you don't know which years were affected by natural events such volcanic eruptions, it can look noisy and confusing.

This is why we need to look at long-term trends to get the real answers.

This post originally appeared on our EDF Voices blog.

Also posted in Basic Science of Global Warming, Greenhouse Gas Emissions, Setting the Facts Straight| Comments are closed
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