Donald Boesch and Virginia Burkett, coastal researchers with Louisiana connections, are widely respected for their expertise on why the state's coast is rapidly being flooded by the Gulf of Mexico, as well as the state's proposed 50-year, $92 billion effort to stop this disaster.
Both believe that recently released research could hold the key to the success of that effort - or its rapid demise.
However, the new study doesn't involve levees, sediment diversions, oil and gas canals or any of the other issues usually debated when Louisiana's coastal plan is discussed.
It concerns Antarctica, thousands of miles south of the Louisiana coast.
The research presents evidence that the world and Louisiana face a stark choice: Keep global temperatures from rising more than 2 degrees Celsius (3.6 degrees Fahrenheit) by 2100, and little will change in Antarctica, which means sea-level rise could be manageable and Louisiana's coastal plan might succeed.
Or fail at that goal, and the result could be a sudden, dramatic melting of ice on Antarctica, adding another 3 feet to the current prediction of a 3.5-foot rise in sea level by 2100 - an event that would swamp most of the southern third of Louisiana, even if the master plan is implemented.
This year's international meeting on climate change in Paris set a goal of reducing carbon emissions to a level that would limit global warming to 2 degrees Celsius.
"Anyone who cares about the future of coastal Louisiana should be very concerned about what happens in Antarctica," said Boesch, a New Orleans native who is president of the University of Maryland Center for Environmental Research. "In many ways, it holds a key to whatever future the coast has."
Burkett is the former head of the Louisiana Department of Wildlife and Fisheries and now the chief scientist for climate and land use change at the U.S. Geological Survey. She agrees with Boesch.
"The rate of ice loss projected for Antarctica could result in the loss of our coastal systems as we know them," she said. "What happens in Antarctica could determine what happens here. We're definitely linked."
The Obama administration has warned the US will need to deal with a wave of "climate refugees" as the Arctic continues to warm, joining with the Canadian government to express alarm over how climate change is affecting indigenous communities.
Sally Jewell, US secretary of the interior, painted a stark picture of communities relocating and lives disrupted in her first official visit to Canada. The Arctic, which is warming at twice the rate of the global average, has just recorded its lowest recorded peak ice extent after what's been called a "warm, crazy winter".
"We will have climate refugees," Jewell said. "We have to figure out how to deal with potentially relocating villages. There's real tangible support we need to do from a government basis, working alongside indigenous communities as they make very difficult choices about what is right for them.
"We can't turn this around. We can stem the increase in temperature, we can stem some of the effect, perhaps, if we act on climate. But the changes are under way and they are very rapid."
The escalating Arctic temperatures, diminishing ice and rising sea levels are having consequences for humans as well as other animals such as polar bears and walruses. The ability to catch fish and travel - or even to hold the famed Iditarod dog sled race in Alaska - is at risk.
Jewell said the remote town of Kivalina in Alaska is "washing away". The coastal town, located around 80 miles above the Arctic circle, has been visited by Barack Obama following warnings its 400-strong population will have to be moved due to thinning ice that exposes the town to crashing waves.
It's a problem that is expected to be replicated elsewhere in Alaska and in Canada. Jewell said political leaders need to "act and support" efforts to make communities more resilient to climate change. US Republicans have, so far, opposed any funding to protect or relocate Alaskan towns.
"The changing climate isn't just about melting permafrost, it's having a huge impact upon cultures," said Catherine McKenna, Canada's environment minister, who met with Jewell in Quebec. "When your ice highway has gone, communities can't interact. It's having a huge impact upon food and food insecurity."
The world's failure to prepare for natural disasters will have "inconceivably bad" consequences as climate change fuels a huge increase in catastrophic droughts and floods and the humanitarian crises that follow, the UN's head of disaster planning has warned.
Last year, earthquakes, floods, heatwaves and landslides left 22,773 people dead, affected 98.6 million others and caused $66.5bn (£47bn) of economic damage (pdf). Yet the international community spends less than half of one per cent of the global aid budget on mitigating the risks posed by such hazards.
Robert Glasser, the special representative of the secretary general for disaster risk reduction, said that with the world already "falling short" in its response to humanitarian emergencies, things would only get worse as climate change adds to the pressure.
He said: "If you see that we're already spending huge amounts of money and are unable to meet the humanitarian need - and then you overlay that with not just population growth ... [but] you put climate change on top of that, where we're seeing an increase in the frequency and severity of natural disasters, and the knock-on effects with respect to food security and conflict and new viruses like the Zika virus or whatever - you realise that the only way we're going to be able to deal with these trends is by getting out ahead of them and focusing on reducing disaster risk."
Failure to plan properly by factoring in the effects of climate change, he added, would result in a steep rise in the vulnerability of those people already most exposed to natural hazards. He also predicted a rise in the number of simultaneous disasters.
"As the odds of any one event go up, the odds of two happening at the same time are more likely. We'll see many more examples of cascading crises, where one event triggers another event, which triggers another event."
Glasser pointed to Syria, where years of protracted drought led to a massive migration of people from rural areas to cities in the run-up to the country's civil war. While he stressed that the drought was by no means the only driver of the conflict, he said droughts around the world could have similarly destabilising effects - especially when it came to conflicts in Africa.
"It's inconceivably bad, actually, if we don't get a handle on it, and there's a huge sense of urgency to get this right," he said. "I think country leaders will become more receptive to this agenda simply because the disasters are going to make that obvious. The real question in my mind is: can we act before that's obvious and before the costs have gone up so tremendously? And that's the challenge."
San Francisco just took a step toward its ambitious goal of relying solely on renewable energy by 2020 with a law that makes it the first major U.S. city to require solar panels on some new buildings, according to its sponsor.
Supervisor Scott Wiener's legislation, passed this week by the Board of Supervisors, is part of the city's efforts to lower emissions and offset climate change.
"By increasing our use of solar power, San Francisco is once again leading the nation in the fight against climate change and the reduction of our reliance on fossil fuels," Wiener said.
California law requires that new buildings less than 10 stories tall include "solar-ready" roof space, meaning 15 percent of the roof must be free from shade and obstructions. The San Francisco ordinance, which goes into effect next year, takes the requirement further by mandating that solar-ready space is actually used for solar panels. Two smaller California cities also require solar panels for new buildings.
The San Francisco ordinance says the solar energy is needed because the city is vulnerable to sea level rise due to carbon dioxide emissions. Solar energy can replace power generated by fossil fuels, reducing those emissions.
"San Francisco is already experiencing the repercussions of excessive CO2 emissions as rising sea levels threaten the City's shoreline and infrastructure, have caused significant erosion, increased impacts to infrastructure during extreme tides and have caused the City to expend funds to modify the sewer system," the ordinance states.
The city's goal is to reduce greenhouse gas emissions by 80 percent of 1990 levels by 2050. The solar panel requirement will lower carbon dioxide emissions for construction currently planned by 26.3 million tons of carbon dioxide annually, according to two former San Francisco environment commissioners who supported the ordinance.
New solar installations are increasing rapidly in the United States, and the cost has fallen dramatically. Solar power still makes up only a tiny fraction of the country's energy production, but it has bigger potential: If solar panels were put on all viable homes, they could supply nearly 40 percent of the country's electricity needs, according to a study from the National Renewable Energy Laboratory. (The study's author notes that filling every inch of sunny roof with solar panels is unrealistic.)
Clean energy has a value in the trillions, Secretary of State John Kerry said at the Bloomberg New Energy Finance conference earlier this month. He compared the economic opportunity with the tech industry's infancy. Kerry also underscored the human and environmental costs of continuing to rely on nonrenewable energy sources.
"Unless we harness the power of the sun, the wind and the oceans, the consequences will be devastating," Kerry said.
Eleven months ago, Houston had a deadly flood. This week, the city had another.
Events like these are often called "100-year floods," and that can be misleading. The U.S. government began using the term in the 1960s to describe a flood that has a 1 percent chance of happening in any given year, not a chance of happening only once a century. It's statistical probability -- and that can change over time.
"Over the span of 30 years, which is the length of many people's mortgages, there is a once in four chance it is going to happen," said Mari Tye, a project scientist in the mesoscale and microscale meteorological laboratory at the National Center for Atmospheric Research in Boulder, Colorado. "Over 100 years, there is a 67 percent chance."
And that doesn't take into account other conditions that can alter the outlook, including changing climate or the effects of El Nino or La Nina.
"That's why the 100-year event is such a moving target, especially in an urban environment," said Chuck Watson, director of research and development at Enki Research, which develops tools to measure hazards. "Someone builds a couple of parking lots, and you just turned a 100-year event into a 70-year event because of the impervious surfaces."
Asphalt doesn't soak up rainwater; it just sends it somewhere else, such as into the house next door. When you add in natural climate cycles, the results are further skewed, Watson said from his office in Savannah, Georgia. One of the influences of El Nino is to send more rain across the southern U.S. In a situation like that, the chances of a catastrophic flood might rise to one in 20.
At least seven people died in Houston in this week's rain, according to CNN. The bulk of the downpour was Monday, when a daily record 9.92 inches (25 centimeters) fell at George Bush Intercontinental Airport, the National Weather Service said. Some areas received more. At least 100,000 customers lost power, the city's light rail was shut and water was over the banks of more than half of its 22 bayous and creeks, which help with flood control.
"If you get that much rain, there is no place for the water to go," said Jill Hasling, who founded the Weather Research Center in the Texas city.
The current flood is worse in some ways than the one last May, Hasling said in an interview at the American Meteorological Society's Hurricanes and Tropical Meteorology conference in San Juan, Puerto Rico. Parts of the city that were dry a year ago are inundated now.
That flood damaged more than 2,500 homes and killed more than 30 people in Texas and Oklahoma, according to reports at the time. A little more than 35 percent of the state had been suffering some level of drought, but by the first week of June the share had dropped to less than 1 percent, the U.S. Drought Monitor reported.
This reveals another problem with trying to quantify extreme events -- things can always get worse, which makes it difficult to come up with a worst-case scenario.
"With all our records, we don't know what the most extreme is, because they are rare," Tye said. "You make an estimate of the probability and then another storm comes along that is worse."
As for Houston, Hasling has some advice: "There's more than one flood a year in Houston. If you live in Houston, buy flood insurance. If you are not in the flood zone, buy it anyway; it will just be cheaper."
Virginia has established a revolving loan fund to help homeowners and businesses make changes to their properties in anticipation of sea-level rise - a step the program's advocates say no other state has taken.
But the distinction comes with an asterisk: There's no money in the fund, and there may not be for several years.
Gov. Terry McAuliffe on Friday signed legislation establishing the Virginia Shoreline Resiliency Fund. Sen. Lynwood Lewis, a Democrat from the Eastern Shore, sponsored the bill, SB282.
It's similar to a program in Connecticut called ShoreUp CT. But that fund and those like it in other states focus on helping applicants deal with current flooding threats. Virginia's program would lend money not just for immediate needs, but also for changes "to mitigate future flood damage" - in other words, sea-level rise.
The Norfolk-based nonprofit group Wetlands Watch worked with Lewis to develop the legislation. Skip Stiles, the group's executive director, said the fund has the potential to accelerate retrofits of buildings in flood-prone areas throughout coastal Virginia.
The Federal Emergency Management Agency provides grants to elevate properties for which multiple damage claims have been made through the National Flood Insurance Program. But that mitigation assistance program is so backlogged that new applicants in this region have almost no chance of getting any money through it in their lifetimes, he said.
In Norfolk, the wait would be 188 years at the pace applications are being processed now, Stiles said. An increase in flooding episodes in recent years led more people to apply for the federal help.
"This is a big problem getting bigger," he said.
New Orleans is the only U.S. metro area considered at greater risk from climate change than Hampton Roads. Scientists have predicted water levels could climb in the region from 1.5 to 8 feet by the century's end, and that was before a study published last month in the journal Nature that warned Antarctic ice melting could cause sea-level rise to accelerate.
Lewis first introduced the legislation in 2015, and Stiles said it was an accomplishment to win bipartisan support for it in this year's General Assembly. Business or home owners would go through their local governments to apply for the low-cost loans, which would be secured by placing liens on their properties. As loans are repaid, money would be freed up to lend to others.
The next step, actually getting money for the fund from the legislature or through a state bond issue, could take three or four years, Stiles said: "But at least now we've got a bucket to put it in."
This week's catastrophic flooding in and around Houston - which claimed at least eight lives, officials reported - calls for climate context.
It's way too early, of course, for any scientific analyses of the sort that researchers call "attribution studies" - attempts to calculate how much, if any, influence manmade climate change may have had on a particular weather event.
Scientists, however, are increasingly pointing in general terms to links between warming temperatures due to carbon pollution, more water vapor in the air, and extreme downpours.
"Near-record atmospheric moisture levels"
"Suffice it to say, this was a very significant flooding storm, and delivered on the near-record atmospheric moisture levels that had been building up over Houston during the last few days," meteorologist and science journalist Eric Berger's Space City Weather blog reported.
The latest Houston inundation, according to an item posted Monday, qualified as that region's "worst flooding event in nearly 15 years, since Tropical Storm Allison [in 2001] deluged the upper Texas coast and dumped in excess of 30 inches of rain over parts of the city."
That blog post didn't address climate change regarding the latest flood disaster to strike Houston, but a prominent Texas climate expert did.