Friday, July 31, 2015

Dry, dry, dry: High Haleakala increasingly arid

Summers high on Haleakala have been getting steadily drier for the past 25 years, according to detailed quarter-century study of the weather on Maui’s dominant mountain.

And that’s just one of the notable trends in the climate of the mountain.

And it is another indicator that Hawai`i can expect a drier future: that natural environments and human water availability will be significantly impacted over time. More on other research in this area below.

The complex study notes that Haleakala has multiple micro-environments: “ecosystems can range from desert, to tropical rainforest, to alpine shrubland over very short distances.”

A key feature of Hawaiian high mountain rainfall patterns is the tradewind inversion. Tradewinds blow across the Pacific, and are driven upward as they hit Island slopes. The rising, cooling air tends to promote rainfall. The paper describes it this way; “On the windward side of the island, trade winds push moist air up the eastern slopes of the mountain, cooling air to the dew point, causing water vapor to condense, forming clouds.”

But this pattern is blocked by the tradewind inversion, a layer of dry, clear and generally warmer air. On Hawaiian high peaks, you can often look down through clear air to the tradewind inversion layer, where the clouds are. The bottom of the inversion layer is the top of the cloud layer.

One result is that there is often far less rainfall on the highest slopes, which are protected from tradewind showers by the inversion layer. They tend to be virtual deserts compared to the rainforests on the middle slopes.

The researchers found that weather has been changing, and specifically, “a significant drying trend is apparent at all of the stations located above 1000 m,” or about 3,300 feet. And that is likely the result of a much more frequent tradewind inversion presence, they say.

To get this data, a team of researchers established 11 climate monitoring stations high on the slopes of the volcanic mountain starting in June 1988. The complex stations collected “solar radiation, net radiation, relative humidity, wind speed, temperature, precipitation and soil moisture, and derived variables including potential evapotranspiration, vapor pressure deficit, soil heat flux and daytime cloud attenuation of sunlight.”

The new report, “Climatology of Haleakala” was prepared by Ryan J. Longman, Thomas W. Giambelluca and Michael A. Nullet, all of the University of Hawai`i Geography Department, and Lloyd Loope, retired researcher with the USGS Pacific Island Ecosystems Research Center. It is Technical Report 193 of the UH Pacific Cooperative Studies Unit.

“The goal of this report is to bring awareness of the climate diversity that exists along the slopes of Haleakalā Volcano and to the changes that are occurring there,” the authors write.

One of their messages: “Changes in moisture may affect vegetation characteristics, promote the spread of invasive species, and decrease water recharge to the aquifers.  These changes are amplified by the time scales by which they are occurring. The faster the climate changes, the less time native species will have to react to these changes and the area in which these species have a competitive advantage may shrink.”

There’s a lot more in this study, and if you’re interested, click on the link above. The full paper is available free online.

The suggestion that rainfall is dropping over time isn’t new. This report is just another brick in that wall.

Earlier this year, Pao-Shin Chu of the University of Hawai`i’s Department of Meteorology published a studyin the International Journal of Climatology, which linked winter drought to El Nino events.

Tim Hurley’s story on the study in the Honolulu Star-Advertiser quoted Chu as saying, “"The planet is changing. You should not assume the weather will remain steady as before. You need to revolutionize your thinking."  

A 2014 report, “Climate ChangeImpacts in Hawai`i,” also sees reduced rainfall.

It is a dense report, readily available online, that includes recitations of many of the impacts of climate change.  With regard to water, there is some spooky stuff.

“Streamflow records also show a decline in base flow over the last century by 20-70%, depending on the watershed, suggesting a decrease in groundwater level,” it says.

“Hawai‘i has experienced longer droughts in recent years, as all the populated islands show an increasing trend in length of dry periods during 1980-2011, as compared with1950 -1970.”

And the tradewinds, which drive a lot of our rainfall? “Prevailing northeasterly trade winds, which drive orographic precipitation on windward coasts, have decreased in frequency since 1973 in Hawai‘i.”

Still, there’s a lot of uncertainty. Some models suggest O`ahu and Kaua`i Counties should get drier and that Maui and the Big Island should get a little more rain due to climate change. (Although the Haleakala study cited above doesn't show that.)  Other models suggest drier winters but slightly wetter summers statewide.

But so far, dry tends to be the trend.

© Jan TenBruggencate 2015

Tuesday, July 14, 2015

Sea level will rise 20 feet--but when?

The most recent reviews of climate change and sea levels lead to important conclusions—sea levels will rise more than we’ve understood, certainly dramatically, even catastrophically…

The threat that emerges from the new research is so immense, so scary, that you’re not seeing it covered in most serious media. Partly, perhaps that's because it seems to outlandish, but also it is because there is still so much uncertainty in the timing.

The likelihood, according to a new study, is of sea levels 20 feet higher than they are now. It has happened before. Indeed, for those of us who have walked the limestone of the ancient coral reefs of Ewa, it's no surprise that sea levels have been far higher than they are now.

The report says those high ocean levels are pretty much baked-in by current greenhouse gas levels and anticipated warming. It’s just not clear when. Could be decades, but it could be centuries. A lot of smart people are trying to figure out which.

“We're debating about timescales that are orders of magnitude different--decades, centuries, a thousand years,” said Andrea Dutton, the new paper’s lead author and a University of Florida carbonate geochemist.

First, some background.

The International Panel on Climate Change in 2007 figured sea levels could be up .2 to .6 meters--almost two feet--by 2100. That would be problematic for low places in the Islands, but perhaps not catastrophic in most places. 

But then the potential impacts of the melting Greenland and Antarctica ice sheets were figured in, and the numbers increased to 1-2 meters, or 3 to six feet by 2100.
During storm periods and super tides, that puts a lot of the coastal areas underwater—badly underwater—including in the Hawaiian Islands. 

Other researchers confirm the suggestion of sea level rise of at least 3 feet. 

This report, published this week in the journal Climate Research by researchers from Denmark, China, Holland and England, comes up with sea level estimates for every major coastal city in Northern Europe. Depending on where you are, and how the land itself moves, the number could be close to 3 feet by 2100, they say.

But they add an ominous warning: “There is a considerable risk that relative sea level rise will exceed recent high-end scenarios.”

And they also warn not to put too much focus on the 2100 level, because planning for that won’t be planning enough: “Sea level rise will continue for centuries beyond 2100, and sea level rise over the 22nd century is projected to exceed that of the 21st century. This long-term aspect should be considered in adaptation plans.”

But another new report, published last week in the journal Science, has thrown all that onto the back burner. 

Based on detailed study of coastal changes in ancient sea level as a result of the warming-caused melting of the globe’s great ice sheets, the authors say there is an excellent chance that even very small amounts of warming—just 1 to 2 degrees—could raise sea levels six meters. 

That’s up to 20 feet above current levels.  That is catastrophic by any standard for coastal communities.

Dutton and her colleagues calculated that the amount of water lost from the immense ice sheets of Greenland and Antarctica is expected in time to be the major contributor to sea level rise. To try to assess their impact,  they studied previous interglacial periods when temperatures were higher than current levels. 

Their finding: "During recent interglacial periods, small increases in global mean temperature and just a few degrees of polar warming relative to the preindustrial period resulted in" as much as 20 feet or more of sea level rise."

And they assess that these levels are probable, because similar temperatures have caused similar sea heights repeatedly in the past. 

RaisingIslands contacted lead author Andrea Dutton at the University of Florida. She said the sea level rise is probably coming, but the researchers still can’t tell how quickly it will arrive. That’s what they’re working on next.

“As we state in the paper, perhaps the most societally relevant information we can provide from the record of past sea-level rise is the rate at which sea level rose as the polar ice sheets retreated. At this stage, the data we have on rates is still highly uncertain and hence is an important target for future research. 

“The physics in the models is not good enough to make projections of rapid ice sheet retreat and/or collapse…There is no consensus on how long it will take. 

"In general, multi-meter sea level rise is thought to take at least centuries, though a model published earlier this year suggested it could be possible over several decades.  So we're debating about timescales that are orders of magnitude different--decades, centuries, a thousand years.  Hence the answer is that it is too uncertain to say,” Dutton said in an email.

What does that mean for people living in coastal areas, and those responsible for planning? 

“From a planning perspective, it would seem to make sense to want to plan for a rate of sea-level rise that is higher than most projections since major storm events will cause extreme sea levels that are even higher than the background rate of rising sea levels,” Dutton said in her email.

Because the impacts of sea levels more than two stories high are so severe the development of better data of global mean sea level (GMSL) is critical, Dutton and her co-authors wrote.

“Improving our understanding of rates of GMSL rise due to polar ice-mass loss is perhaps the most societally relevant information the paleorecord can provide, yet robust estimates of rates of GMSL rise associated with polar ice-sheet retreat and/or collapse remain a weakness in existing sea-level reconstructions,” they wrote.

How does a community plan for something like this? In Hawai`i, consider that at the predicted levels, most of our airports are underwater, most of our harbors are gone, most of our resort areas are awash, many of our water wells turn salty. Sewer lines, power plants, coastal roads are destroyed, and many communities on almost every island are isolated.

Most of the Northwestern Hawaiian Islands and most of the atolls and other low-lying islands throughout the Pacific would be gone. The impacts on the turtles, seals and millions of nesting seabirds are beyond imagining.

© Jan TenBruggencate 2015

Monday, July 13, 2015

Collapsing seabird populations--down 70% in 60 years.

Seabird populations have dropped by two-thirds in the past 60 years, and may have dropped significantly even before that.

Recent studies suggest that the winged wonders that soar over the oceans are dramatically fewer than they were long ago.

(Image: Albatross numbers are down. Credit: NOAA.)

Many of the seabirds around the Hawaiian Islands lay their eggs and raise their young on the islands. 

Some islands, notably the ones in the Northwestern Hawaiian Island archipelago, are still dense with nesting birds. Around the Main Hawaiian Islands, not so much. 

But they once were nesting in massive colonies here, as well, said Storrs Olson, the famed paleoornithologist at Smithsonian Institution. Olson said bird flocks flying out to sea from those colonies would have been so dense that any early voyagers would have easily found the Hawaiian Islands if they’d gotten within a few hundred miles.

But most of those Main Hawaiian Island colonies have been lost to habitat destruction and predation.

In modern times, the decline in bird populations continues. 

Researchers from the University of British Columbia reported that during the last 60 years, monitored populations of seabirds have declined 70 percent. Their work was published in the journal PLOS One. Here is Eurekalert’s printing of the university’s press release. Here's Science Daily's version.

They didn’t look at all seabirds—not all seabirds are being monitored--but their work represented studies of 500 populations worldwide, which represent 19 percent of all seabirds. 

Lead author Michelle Paleczny, a UBC master's student and researcher with the Sea Around Us project, said overall populations had dropped  69.6 per cent in the 60-year period from 1950 to 2010, equivalent to a loss of about 230 million birds.

“The largest declines were observed in families containing wide-ranging pelagic species, suggesting that pan-global populations may be more at risk than shorter-ranging coastal populations,” the authors wrote. Those pan-pelagic species would include birds like albatrosses.

We are losing the birds to a variety of threats. The authors cite entanglement in fishing gear, overfishing of food sources, climate change, pollution, disturbance, direct exploitation, development, energy production, and introduced species like cats, dogs and other predators on nesting sites that once lacked these predators. 

These are familiar stories in Hawai`i, where we regularly see stories of nesting seabirds like shearwaters, albatross and petrels being attacked on their nests by pigs, rats, cats and dogs.

The health of seabird populations is important because, as wide-ranging species, they can open a window to the health of the oceans.

“Seabird population changes are good indicators of long-term and large-scale change in marine ecosystems because seabird populations are relatively well-monitored, their ecology allows them to integrate long-term and large-scale signals (they are long-lived, wide-ranging and forage at high trophic levels), and their populations are strongly influenced by threats to marine and coastal ecosystems,” the authors wrote.

© Jan TenBruggencate 2015

Citation: Michelle Paleczny, Edd Hammill, Vasiliki Karpouzi, Daniel Pauly. Population Trend of the World’s Monitored Seabirds, 1950-2010. PLOS ONE, 2015; 10 (6): e0129342 DOI: 10.1371/journal.pone.0129342

Wednesday, July 1, 2015

The Maui GM Ordinance preemption ruling: A deeper look.

There are lots of fascinating tidbits in federal Distric Judge Susan Oki Mollway’s rejection of the Maui GMO ordinance.

And lots of things left undecided—things to give hope to both sides in the dispute. More on that later.

The essence of Mollway’s ruling was that Maui County can’t enforce the GMO ban, because it would intrude on the authority of both the federal and state governments, and that its civil fine provisions are clear violations of the county’s authority.

The judge refers to the federal Plant Protection Act, which prohibits bringing across state lines genetically modified plants that have been developed using known weeds. If genetically modified plants aren’t weeds, they are permitted, the act says. 

Since the Maui ordinance prohibits all GM plants, it prohibits ones that are permitted under federal law.

“If the ordinance conflicts with (the Plant Protection Act) then the ordinance’s conflicting provisions are preempted…,” the judge wrote.  “Maui’s ban of GE organisms run afoul of the Plant Protection Act and its regulations,” she wrote.

She goes on to say that the Maui ban violates the Plant Protection Act’s “purpose of setting a national standard governing the movement of plant pests and noxious weeds in interstate commerce based on sound science.”

On the issue state preemption, the judge said the state Constitution clearly delegates to the state Legislature the authority to protect agricultural lands, and that the state Legislature clearly delegates to the state Department of Agriculture “authority to oversee the introduction, propagation, inspection, destruction and control of plants.”

The opponents of the Maui bill argue that the Department of Agriculture has a clear and thorough regulatory system in place that preempts the Maui bill. The supporters of the Maui bill say it’s a mere “patchwork” of regulations. Mollway seemed satisfied that the state’s regulatory system is sufficient to prevent the county from stepping in.

On a third major point, Judge Mollway said the fines imposed under the Maui bill violate both the county Charter and state law--largely because the fines are way too high. “The civil fine provisions are unenforceable,” the judge wrote.

While the Maui GMO ban is clearly defeated, Judge Mollway left intriguing hints about possible additional arguments for both sides—arguments she said she didn’t need to address since the preemption and illegal fine issues were clear enough.

Supporters of the ban have cheered her insistence that her ruling is entirely on legal grounds, not on the inherent value or danger of genetic modification of food plants. “No portion of this ruling says anything about whether GE organisms are good or bad or about whether the court thinks the substance of the Ordinance would be beneficial to the county.”

Does this mean Mollway might have an opinion about whether GE organisms ought to be controlled? No clue. She's not saying.

The other side can draw strength from the fact that there were several arguments favorable to the seed industry that Mollway didn’t feel she needed to research.

Mollway said she did not even need to look into whether the EPA’s experimental use permits, which have been issued to Monsanto, also preempt the Maui bill. 

She said she didn’t need to get into whether state pesticide laws also preempt the ordinance. 

And she said she didn’t need to determine whether the Commerce Clause of the U.S. Constutition preempts the ordinance.

In a little dig at the anti-GM folks, Mollway criticized a tendency to assert things without bothering to back them up. The court ruled that you can’t refute a stated fact without evidence—meaning you can’t simply say it isn’t true. You need to show it isn’t true.

In one case, the GM opponents—the group calling itself SHAKA—even denied that Maui County is a political subdivision of the state. Mollway chided the group for violating court rules by “generally denying the facts without citation of any evidence and by including immaterial additional facts.”

On the same issue, Joan Conrow has an excellent article at her blog site. It looks at the issues from a slightly different perspective. Find it here. 

© Jan TenBruggencate 2015