Wednesday, March 20, 2019

A Sea Level Rise Conundrum – Greenland’s Cycles

After France fell to the Nazis, Britain desperately prepared for an invasion. The United States shuttled hundreds of planes to England via the Snowball Route, a series of secret bases on Newfoundland, Greenland and Iceland. But in 1942 one squadron never completed the journey. A sudden July storm forced 8 planes to land on a slushy glacier surface in southeast Greenland. Although the crews were rescued, later attempts failed to locate the Lost Squadron. The glaciers had ferried the planes miles downstream as they were increasingly buried in ice. One plane was finally recovered in 1992 and the second, recovered in 2018, was under more than 300 feet of ice. Southeastern Greenland had been gaining ice at a rate of 4 feet per year. 

In contrast, climate scientists project Greenland will increasingly lose ice as CO2concentrations increase. Indeed, its melting ice has been the biggest contributor to accelerating sea level rise for 2 decades.  But that is rapidly reversing. City planners along California’s coast are struggling with competing theories. How much sea level rise should we plan for?  Fearing an accelerating rise, some argue we abandon the coast. Others argue, and I agree, we should protect our homes with seawalls. But how high must we build? Understanding Greenland’s contribution is critical.

If we removed all ice from Greenland, the land would reveal a bowl-shape. A ring of mountains paralleling the coastline prevents the ice cap from sliding into the sea, no matter what scary climate stories suggest. Several gaps in those mountains allow glaciers to transport ice from inside “the bowl” to the oceans. Given enough time the Lost Squadron may well have been shuttled out to sea. Whenever more ice accumulates inside the “bowl” than leaks out via glaciers, Greenland gains ice and sea levels fall.  If more ice reaches the ocean than accumulates inland, sea level rises. But predicting any imbalance is difficult.

During the last 100 years, Greenland oscillated between gaining and losing ice. Its greatest loss raised sea level by 0.07 inches in 2012, about half the total sea level rise of 0.12 inches a year. That accelerated loss was trumpeted as just what climate models predict. However, Greenland’s melt rates then declined and by 2017 it was gaining enough ice to slightly reduce sea level rise.

Furthermore, the cause of rapidly melting ice since the 1990s was fewer clouds. Fewer summer clouds allow more solar heating and cycles of atmospheric circulation naturally alter cloud cover. In addition, researchers reported Greenland’s ice-free regions experienced various warming and cooling trends over the past 15 years, but concluded if there was any general trend, “it is mostly a cooling”. They also admitted they “cannot differentiate between anthropogenic forcing [in other words: warming from human added CO2] and natural fluctuations.”

A similar warming and melting episode occurred decades earlier. Climate scientists determined Greenland had warmed most rapidly between 1920 and 1940. As reported by the IPCC, “temperature has risen significantly since the early 1990s, reaching values similar to those in the 1930s.”Regards accelerated rates of sea level rise from melting ice, the IPCC reported “It is likely that similarly high rates occurred between 1920 and 1950.”  Intriguingly, much lower CO2concentrations still resulted in similar warming, melting and rates of sea level rise.

Until Greenland’s temperatures and ice-melt exceed the 1930s episode, scientists cannot distinguish between natural variability and human-caused warming. The current trend is too short to be certain, but the past 2 years suggest Greenland is now entering a cooling cycle. In fact, based on my analyses of published scientific reports regards decades-long cycles of migrating fish into and out of the Arctic, and circulation effects of Atlantic oscillations, I boldly blogged in 2014, we would soon see Greenland begin to gain ice, as it is now doing.

Of course, that prediction was attacked by the ill-informed. They claimed my analyses of published scientific observations was cherry-picking, pseudo-science and I ignored the (mythical) 97% consensus.  My response is always, there is absolutely no consensus regards climate’s sensitivity to a doubling of CO2. Some IPCC experts predict 1 degree warming, others predict as much as 5 degrees. Nonetheless the scientific method demands, to prove rising CO2is causing an effect like melting Greenland ice, we must show current changes exceed past natural variability. But most people are unaware that has yet to happen. 

We are an adaptable people. Seawalls we build to protect our coastal homes for the next hundred years, likely need to plan for just 8 inches of sea level rise, but certainly not 5 or 10 feet. Yet to be confident, we need another 20 years to determine the contribution of natural cycles.

Jim Steele is retired director of the Sierra Nevada Field Campus, SFSU

Wednesday, March 6, 2019

Scary Climate Campfire Stories

Scary Climate Campfire Stories

Several politicians and a few scientists tell us we are facing a climate crisis. They warn if we do not act now, we’ll leave our children an uninhabitable world. Naturally nobody wants that. But throughout history, the public has been bamboozled by various “end of the world” stories. I’m reminded of the Heaven’s Gate Cult. Highly educated members were conned into believing a spaceship, hiding behind the approaching Hale-Bopp comet, was coming to save them from our deteriorating world. On March 26, 1997, 39 followers committed mass suicide. Its disturbing how easily end of the world fears override basic critical thinking. 

My whole professional career I’ve advocated for wise environmental stewardship. My research in the Sierra Nevada restored a watershed and increased wildlife. I’ve warned that landscape abuse destroys ecosystems. I’ve pointed out how over-hunting and invasive organisms endanger species. I’ve noted island extinctions occurred when humans imported rats, cats and mosquitoes that attacked ill-prepared native species. But, in contrast to abundant media hype, I have yet to verify a single climate-change induced extinction. 

Understandably, to most people, a one degree change in global temperature over the past 150 years, does not seem fatal. I studied micro-climates. Over a distance of a few hundred feet from bare ground to forest shade, summer temperatures will vary by over 20 degrees. We endure a greater temperature change between night and day. Still some scientists and politicians push a narrative that just a one-degree change in global temperature over a period of 100 years has been deadly. But what’s their evidence?

The first highly publicized climate “tragedy” was Camille Parmesan’s claim that global warming had caused population extinctions that pushed California’s Checkerspot butterfly’s range northward and upward. Such a catastrophic assertion attracted the Intergovernmental Panel on Climate Change (IPCC). So, Parmesan became one of just 4 biologists on the IPCC in 2001. The Union of Concerned Scientists’ website also hyped Parmesan as a climate change heroine! In contrast, every other butterfly researcher argued it was California’s growing sprawl and resulting landscape changes that decimated the Checkerspot’s prime habitat.

Hoping to separate landscape changes from climate change, I tried to replicate Parmesan’s iconic study. But she never published her data. In a gross violation of scientific process, she refused to share her data. We battled, but it was finally admitted many populations that she had claimed had been extirpated by climate change, were now thriving. Unfortunately, such good news was never publicized. That was my first taste of dishonest climate fear-mongering. 

In 2010 so-called experts suggested polar bear populations were declining. They claimed global warming would extirpate two thirds of all polar bears by 2050. But today no populations are in decline. Basic biology argues less sea ice allows more photosynthesis which increases plankton abundance. More plankton support more fish and seals, which in turn feed more polar bears. Like the Inuit who steadfastly claim it is the “time of the most polar bears”, my 2012 analyses found polar bear populations were increasing. Accordingly, the global population has now increased from about 25,000 to 30,000 and researchers from Norwayto Alaska are reporting very fat polar bears.

Fat Polar Bears

In Antarctica, a few scientists hyped penguins were “marching to extinction.” In 2009 both Emperor and Adelie penguins were considered healthy and “species of least concern”. Oddly, despite larger populations, both species were downgraded in 2012 to “near threatened” based only on climate change predictions. Nonetheless with the discovery of new colonies and the robust growth of known colonies, Adelie penguin abundance increased from 4 million to 8 million. Perhaps climate change benefitted Adelie penguins? So, in 2016 experts reverted their status back to “species of least concern”.

Elsewhere a few scientists argued global warming was pushing adorable rabbit-like pikas off mountain tops into extinction throughout the western USA.  Instead, further research proved pikas are actually expanding into lower and warmer elevations. 

In 2008 climate scientists claimed children would no longer know what snow is. Yet in 2019 snowfall from Hawaii to Wisconsin has been breaking records. Inconsistent with global warming theory, in the northern hemisphere, winter and autumn snow cover has increased. Only spring-time snow cover has decreased.

For several decades, bogus catastrophic climate-change claims have come and gone. Claiming the world is destined for climate hell in 12 years is just another scary campfire story. In contrast, scientists are observing that rising CO2has a fertilization effect promoting a greening of our planet! If we truly care about nature, rising CO2is not the problem. There are far more important problems to address!  Detrimental changes to our ecosystems are driven by overhunting, invasive species and loss of habitat.