Saturday, July 23, 2016

Where Are the Hurricanes?


After 1998 when rising global temperatures of the past two decades became clear, the temperatures have flat lined for twenty years during which the CO2 content has climbed significantly.   This alone eliminates any argument regarding tentative linkage.

What is nice is that it is warm.  The retreat will not be nice and will likely be abrupt.  A full degree can be imagined if past reports are listened to.

Again it must be remarked that there is a super cycle with hurricane seasons of around forty years, obviously linked to a slow drift around the globe as the actual numbers globally do not decline. In fact hurricanes look to be a steady heat release mechanism that shows remarkable stability, just like our Holocene climate..

Where Are the Hurricanes?

THE United States coastline has been calm so far this hurricane season, just as it has been over the last decade. Since 2005, the year of Hurricanes Katrina, Rita and Wilma, the country has been in a hurricane “drought,” with no major hurricane (Category 3 or above, meaning winds above 110 miles per hour) making landfall. The nation’s most hurricane-prone regions, the Southeast and Gulf Coasts, have been eerily quiet.

Even so, climate scientists like me believe that human-induced climate change will strengthen hurricanes and lead to worse disasters. We know that significant global warming, over a degree and a half Fahrenheit, has already occurred since preindustrial days. So where, you might ask, are the powerful hurricanes?

They’re coming, if we don’t take more aggressive action to slow climate change.

What we have seen recently is consistent with our scientific understanding of hurricanes and climate. That knowledge is far from perfect, but the prediction of stronger future hurricanes is not contradicted by the data thus far.

The Atlantic Ocean, where hurricanes affecting the United States arise, generates only a little over 10 percent of the planet’s tropical cyclones, a term that includes both hurricanes and less intense but still powerful tropical storms. What happens in the Atlantic isn’t generally representative. In fact, other regions have not enjoyed the vacation that our most susceptible coastlines have had from serious storms. Ask the people in Taiwan and China, who just got hit by a supertyphoon named Nepartak (“supertyphoon” is, approximately, the western Pacific label for what we would call a major hurricane).

There is also large natural variability, in the Atlantic and elsewhere. Some hurricane seasons are active and some aren’t. The fluctuations occur not just year to year but even decade to decade and longer. The current hurricane drought is one such fluctuation. While there is debate about the drought’s significance, there is little doubt that its primary cause is dumb luck, and that won’t continue forever.

The best science doesn’t, in fact, predict that the future will hold more hurricanes; most of our best models predict there may be fewer. But these predictions of changes in the number of hurricanes are quite uncertain, in part because they are connected to a more basic problem: Why does the number of tropical cyclones average about 90 per year, and not more or fewer?

We don’t really know.

But when it comes to the strength of hurricanes, we have a pretty good comprehension of the physical science of how hurricane intensity is controlled by the large-scale climate. In a paper this week in the journal Science, several colleagues and I assess the state of this understanding and what it implies about the recent past, present and future of hurricanes.

As the climate warms, the physics says hurricanes should get stronger, because the tropical ocean surface heats up more than the atmosphere above it, increasing the temperature differential on which storms feed. The best computer models also predict stronger storms, so we have separate but consistent lines of evidence. Even if the number of hurricanes decreases somewhat, the overall increase in intensity may well mean that there are more of the strongest storms. And the very strongest storms of the future will probably exceed any of the past in their intensities.

While several groups of scientists who have done statistical analyses of data on all storms for the last few decades have found significant increases in the numbers of the strongest ones, Categories 4 and 5, it is also true that those results are not consistent across all studies.

It also turns out that human influence on storm intensity is more complicated than we have thought. Human activities have not just increased atmospheric concentrations of greenhouse gases, but also concentrations of aerosols — tiny liquid or solid particles from cars, industrial smokestacks and fires. These particles tend to cool the climate by absorbing and reflecting sunlight, though they haven’t been enough to prevent significant global warming over the last century.

But aerosol cooling appears to be disproportionately effective in reducing hurricane intensity, and climate models suggest that, because of the aerosols, hurricane intensity globally should not have increased much yet, despite warming caused by greenhouse gases.

But it isn’t likely to stay that way.

Global aerosol concentrations appear to have reached something of a plateau, thanks to air quality regulations in the United States and Europe. While increases in aerosol emissions in Asia have offset the decline elsewhere, this pollution is unlikely to keep pace with rising greenhouse gas emissions. Moreover, aerosols tend to wash out after a few weeks, while carbon dioxide stays in the atmosphere for a very long time.

Barring global emissions reductions much larger than anything agreed on in the Paris climate accord (or the development of carbon-capture technology on a significant scale), greenhouse gas concentrations will continue to increase. And without the compensating effect of increasing aerosol emissions, the warming of the future, more than the warming of the recent past, will strengthen the most powerful and destructive storms that the planet can produce.

Warmist Tries to Justify 11-year Hurricane Drought in New York Times Op-Ed

By: Marc Morano - Climate DepotJuly 15, 2016 2:42 PM

The New York Times ran an op-ed today by Adam Sobel, an “atmospheric scientist at Columbia.” The gist of Sobel’s article: Since 2005, the United States has been experiencing a hurricane “drought” (i.e., no category 3 or higher hurricane has made landfall in 11 years.) But don’t worry, Sobel says, there will be more hurricanes soon, and the fact that they will be coming is proof of man-made climate change.

Yes, that’s what he’s saying.

The question is whether Sobel is writing the op-ed to buck himself up, or hoping to cheerlead the rest of the alarmist crowd. After all, the computer models that have predicted global warming have also predicted more hurricanes. But real-life observations continue to diverge from what computer models have actually predicted.

It’s somewhat baffling that the New York Times would publish such an essentially meaningless opinion. But the mainstream media have long since thrown in its lot with the alarmist crowd.

Regardless, there are problems with Sobel’s op-ed…

Sobel says that “significant global warming, over a degree and a half Fahrenheit, has already occurred since preindustrial days.” That’s essentially accurate. The Earth has warmed by roughly 0.8 degrees Celsius since the late 1800s. But whether one views it as “significant” depends on context. Given the accumulatingevidence of global climate changes over the past few thousand years, such a net increase over a span of roughly 130 years seems relatively mild—and typical of the climate variations seen during the latter part of the current interglacial epoch.

There’s also the greater issue of cause. Sobel naturally assumes that this increase in temperatures is driven entirely by increased emissions of carbon dioxide (CO2). But many climate skeptics would argue that this mild uptick is the result of a large-scale increase in solar output over the past 130 years. And while solar irradiance has increased in that time, it is the associated variations in solar winds and the solar magnetic field that contribute significantly to changes in global climate, thanks to their influence on atmospheric ionization and cloud formation.

No comments: