Four amazing and passionate scientists discussed different aspects of our changing world—wildlife, drought, storms and the tree-ring record—at a press conference titled, “Did Climate Change Cause Superstorm Sandy?”

Remember, these are scientists, not politicians (see more in Andy Revkin’s New York Times blog). They need evidence to see causal effect between one event and another. And for these recent storms and weather patterns, there just isn’t enough evidence. Yet.

But are these researchers glad that these events are focusing Americans’ attention (including the President in his recent State of the Union address) on climate change? Most definitely. Yes.

Here’s what they do know. Climate change is affecting the probability of storms like Sandy and Nemo. There is evidence that in our warming world, severe storms will happen more frequently.

Researchers understand that global warming and other human-related activities are affecting where animals live, move and mate, and when plants bloom.

Scientists also know that temperature increase is one factor in drought. Texas temperatures have risen steeply in just the past 15 years and drought has increased.  And now Texans are talking about climate change, said John Nielsen-Gammon of Texas A&M University. The drought alone didn’t alarm them about climate change, but the decreased water supply has made people and politicians alike take notice.

And the speakers are hopeful and passionate that we’ll start doing something about these effects—reducing fuel emissions, restoring habitats, becoming more aware of climate change.

What do you know and feel? Share with us here.

Midwest drought image: cwwycoff1/Wikipedia

A recent article in PLoS ONE takes the naturalists’ records and compares plants’ blooming times from then to now—specifically 2012, with its record-breaking temperatures.

Not surprisingly, plants are blooming earlier. Previous research has demonstrated this, but not with specific places and plants.

Compared to the timing of spring flowering in Thoreau’s day (in the mid-1800s), native plants such as serviceberry and nodding trillium are blooming 11 days earlier, on average, in the area around Concord, Massachusetts, where Thoreau famously lived and worked.

Nearly a thousand miles away in Wisconsin, where Leopold gathered his records of blooming plants like wild geranium and marsh marigold, the change is even more striking. In 2012, the warmest spring on record for Wisconsin, plants bloomed on average nearly a month earlier than they did just 67 years earlier when Leopold made his last entry.

“We were amazed that wildflowers in Concord flowered almost a month earlier in 2012 than they did in Thoreau’s time or any other recent year,” says lead author Elizabeth Ellwood, “and it turns out the same phenomenon was happening in Wisconsin where Aldo Leopold was recording flowering times. Our data shows that plants keep shifting their flowering times ever earlier as the climate continues to warm.”

I asked Peter Fritsch, curator and chair of the Academy’s Botany Department, about the recent paper.  “The study makes clear that the strong link between increasing spring temperatures and earlier flowering times holds even during the hottest years known; other factors, such as unmet winter chilling requirements, appear not to have constrained or disrupted this link. Whether this link continues at even higher temperatures remains to be seen.

“Although this could mean that plants will be able to continue fairly normal patterns of reproduction, albeit at earlier and earlier times,” he adds, “other environmental factors, some of which could be critical to plant species’ survival, will likely be changing as well. For example, insect pollinator or seed disperser activity may become reduced or mistimed relative to flowering or fruit set.”

The new PLoS ONE study reminded me of the Grinnell Resurvey Project, where UC Berkeley scientists revisited locations documented by Joseph Grinnell a century ago. Grinnell thoroughly recorded fauna in several locations in California and modern-day researchers could document changes from his original observations. Peter says that he knows of no directly comparable studies in our area, that is, those that have looked at the changes in California flora and blooming time over such a long period of time.

Thoreau and Leopold (and Grinnell, for that matter) likely had no idea their records would prove to be so helpful in this particular way, decades later, Peter says. “This study also provides neat insight into one way that science works. In this case, I doubt very much whether it would have occurred to Thoreau that the notes he was recording on flowering times could be used for assessing long-term changes in climate. Yet, without his basic data and that from Leopold, the current study would not be nearly as conclusive.”

One last note from Peter: One of the co-authors on the study, Charles Davis, has Academy ties. He was a Summer Systematics Institute intern in the 1990s!

Yesterday, James Hansen of NASA’s Goddard Institute and Thomas Karl of NOAA’s National Climatic Data Center held a joint press conference, describing very similar findings for last year’s warmer than average temperatures around the world. A pdf with their organizations’ side-by-side comparisons is available here.

The average temperature globally in 2012 was about 58.3 degrees Fahrenheit, which is 1.0 F (0.6 C) warmer than the mid-20th century baseline. The average global temperature has increased about 1.4 degrees F (0.8 C) since 1880, according to the new analysis.

The scientists emphasized that weather patterns always will cause fluctuations in average temperature from year to year, but the continued increase in greenhouse gas levels in Earth’s atmosphere assures a long-term rise in global temperatures. Each successive year will not necessarily be warmer than the year before, but on the current course of greenhouse gas increases, scientists expect each successive decade to be warmer than the previous decade.

“The U.S. temperatures in the summer of 2012 are an example of a new trend of outlying seasonal extremes that are warmer than the hottest seasonal temperatures of the mid-20th century,” Hansen said. “The climate dice are now loaded. Some seasons still will be cooler than the long-term average, but the perceptive person should notice that the frequency of unusually warm extremes is increasing. It is the extremes that have the most impact on people and other life on the planet.”

In fact, according to Reuters, Americans are feeling the impact of climate change already—consequences that affect “health, infrastructure, water supply, agriculture and especially more frequent severe weather.”

But studies show we can do something about it. Nature Climate Change has an article this week describing how cutting emissions can reduce impacts from climate change. (Read more at Scientific American.) And New Scientist reports that while global talks breakdown over the subject, individual nations are doing something about it. Let’s hope the trend continues.

Want to engage more in the changing climate? Tomorrow Science will host a live chat, “Can We Conquer Climate Change?” Sign in here.

Image: NASA Goddard’s Scientific Visualization Studio

Another climate and water story

Last week, we featured a series of stories on climate change and water issues and this one slipped by. A study in Nature last week reported how trees physically respond to drought. And the news is not good. Plants undergoing drought stress experience reduced pressure in the xylem (the vessel that transports water from the soil to the leaves).

Head over to NPR to read (or listen to) their piece on the study.

Melting ice sheets and sea level rise

A NASA/ESA study, published in Science this week provides the most thorough representation of the rate of melting ice sheets and corresponding sea level rise to date. Using extensive satellite data, scientists report that the ice sheets covering Greenland and Antarctica are losing more than three times as much ice each year as they were in the 1990s. About two-thirds of the loss occurs from Greenland, with the rest from Antarctica.

Combined, melting of these ice sheets contributed 0.44 inches to global sea levels since 1992. This accounts for one-fifth of all sea level rise over the 20-year survey period. The remainder is caused by the thermal expansion of the warming ocean, melting of mountain glaciers and small Arctic ice caps, and groundwater mining.

“Both ice sheets appear to be losing more ice now than 20 years ago, but the pace of ice loss from Greenland is extraordinary, with nearly a five-fold increase since the mid-1990s,” NASA’s Erik Ivins says.

Ocean acidification and fighting back

Ocean acidification is already having an effect on marine life, according to a study published this week in Nature Geoscience. Shells of live mollusks from the Southern Ocean are showing signs of “severe dissolution.” New Scientist has more information.

Washington State is taking action to curb ocean acidification and protect the state’s large shellfish industry. A report, released this week, outlines plans to target pollution that causes acidification (including carbon emissions and agriculture run-off) and has a $3.3 million backing. More information is available here.

Maybe more coastal states (and nations) will follow Washington’s lead, says the Ocean Conservancy.

A Sad Factoid

A final thought from the editors at grist.org, who note that “if you’re 27 or younger, you’ve never experienced a colder-than-average month.” A truly sobering fact gleaned from the NOAA “State of the Climate” report for October 2012.

Image: Ian Joughin

For scientists, policy-makers and organizers who frequently discuss climate change, the last few years have been rough! While they still may be discussing it amongst themselves, with the economic downturn, a larger audience has been absent. An episode of Frontline explores the massive shift in public opinion on climate change.

But the last two weeks might change all of that.

Hurricane Sandy affected so many people that climate change popped up in many new conversations. Click on these questions to find some of these headlines:

• Was the storm caused by climate change?
• Are humans to blame?
• Will global warming bring more “frankenstorms” like Sandy?
• How can cities protect themselves?
• What are some of the financial impacts?
• How can communities adapt to a new normal of storms like these?
• How do we find stormproof solutions?

Will Obama’s second term allow him to speak more freely (and more urgently) about climate change? Scientific American says that we’ll likely only see “more of the same.” But New Scientist has some suggestions about how he can create a “climate change legacy.” And Brandon Keim, in Wired, sees opportunity for the President:

A cap-and-trade system for carbon pollution is unlikely, but other approaches are possible, from adapting infrastructure and improving post-disaster resilience to revenue-neutral carbon taxes and reduced fossil fuel subsidies.

Let’s hope these conversations start quickly (the Academy’s Peter Roopnarine blogs about climate change, providing many conversation starters). According to recent news headlines (here and here), we’re quickly looking at worst-case scenarios for global warming.

What do you want to say about climate change? Share below.

Image: NOAA

It all has to do with an experiment in the Indian Ocean in 2004. Scientists dumped seven tonnes of iron into an eddy in the Southern Ocean. As expected, an algal bloom followed. Scientific American describes this well:

A hunger for iron rules the microscopic sea life of the Southern Ocean surrounding ice-covered Antarctica. Cut off from most continental dirt and dust, the plankton, diatoms and other life that make up the broad bottom of the food chain there can’t get enough iron to grow.

The bloom was dominated by diatoms like the one pictured above. This group of algae are known to form large, slimy aggregates (marine snot) with high sinking rates at the end of their blooms. Indeed, after about a month, over 50% of the bloom sank deeply into the ocean, taking carbon dioxide with it as it went.

Science News quotes Victor Smetacek, lead author in the study, as saying:

“Every one atom of iron removed 13,000 atoms of carbon” from the air.

While scientists suspected this, they were never able to prove it. This is likely what happened during past ice ages. The air was cooler and drier then and carried more iron-containing dust from the continents to the ocean—lavishly supplying marine phytoplankton and removing carbon, cooling the atmosphere.

Now scientists are wondering if we can cool our warming climate by simply adding iron to the ocean. National Geographic has more on this geoengineering fix and other extreme geoengineering ideas to fight global warming. If only we spent this much energy on stopping global warming…

Image: Marina Montresor, SZN, Alfred Wegener Institute

Most of us know that global warming wreaks havoc on our planet. Climate scientists make dire predictions of what is in store for us, but some aren’t ready to throw in the towel just yet. In a study published in last week’s Science, an international team of climatologists predicts that not all our planet’s environments will suffer from the effects of global warming. In fact, some might be doing just fine.

Carlos Jaramillo, climatologist for the Smithsonian Tropical Research Institute (STRI), and his colleagues analyzed fossilized pollen dating to more than 50 million years ago. What makes this time frame so important? In one of the most dramatic warming events in Earth’s history, annual temperatures increased by three to five degrees Celsius in only 10,000 years, an unprecedented shift. Jaramillo and his team wanted to see if rainforests survived the heat wave during this period, known as the Paleocene-Eocene Thermal Maximum.

Upon analyzing the preserved pollen, they had expected to see reduced numbers and lower diversity of plant life. After all, how could the delicate plants and flowers that make up the rainforest endure such a remarkable rise in temperatures?

But the team’s observations showed that plants endured—and thrived. Their analysis actually revealed increased diversity of tropical plant life. New species of plants seemed to crop up everywhere. For example, the earliest ancestors of the passionflower and cacao plant appeared for the first time in history. If Earth really was hotter 50 million years ago, the rainforests seemed to relish in it.

Does this mean we should stop worrying about global warming? Hardly. Human impacts on our environment, including deforestation and pollution, combined with global warming, will still have unfortunate effects on most of Earth’s ecosystems. But we have learned that, even when faced with extreme temperatures, some of our most fragile environments will find a way to survive.

Anne Holden, a docent at the California Academy of Sciences, is a PhD trained genetic anthropologist and science writer living in San Francisco.

Creative Commons image by ggallice

These microscopic marine algae form the basis of the marine food chain and sustain a number of diverse species ranging from tiny zooplankton to large marine mammals, seabirds, and fish.

“Phytoplankton is the fuel on which marine ecosystems run. A decline of phytoplankton affects everything up the food chain, including humans,” according to Daniel Boyce the lead author of a new study published in the July 29th edition of Nature.

The cause of the phytoplankton decline? Rising ocean temperatures.

Ed Yong in Discover writes that:

Phytoplankton need sunlight to grow, so they’re constrained to the upper layers of the ocean and depend on nutrients welling up from below. But warmer waters are less likely to mix in this way, which starves the phytoplankton and limits their growth.

Using an unprecedented collection of historical and recent oceanographic data, Boyce and his team documented phytoplankton declines of about 1% of the global average per year. Again, from Discover:

Boyce’s study… really began in 1865, when an Italian priest and astronomer called Father Pietro Angelo Secchi invented a device for measuring water clarity. His “Secchi disk” is fantastically simple—it’s a black-and-white circle that is lowered until the observer can’t see it any more. This depth reveals how transparent the water is, which is directly related to how much phytoplankton it contains. This simple method has been used since 1899. Boyce combined it with measurements of the pigment chlorophyll taken from research vessels, and satellite data from the last decade.

The scientists found that long-term phytoplankton declines correlated directly with rising sea surface temperatures and changing oceanographic conditions. Their data also matched fluctuating weather patterns such as El Niño.

While rising ocean temperatures may contribute only partly to the phytoplankton decline (articles in Nature and the BBC also mention ocean circulation, wind and over-fishing), we should pay attention. For phytoplankton not only feeds the seas, it also, according to the BBC, sustains all life. “Photosynthesis by phytoplankton removes carbon dioxide from the air and produces oxygen.”  And right now, we can use all the carbon dioxide removal we can get!