Category Archives: Climate

Solar dimming can trigger freezing winters: study
David Fogarty

A cyclical drop in the sun’s radiation can trigger unusually cold winters in parts of North America and Europe, scientists say, a finding that could improve long-range forecasts and help countries prepare for blizzards.

Scientists have known for a long time that the sun has an 11-year cycle during which radiation measured by sunspots on the surface reaches a peak then falls. But pinning down a clear link to weather has proved harder.

“Our research confirms the observed link between solar variability and regional winter climate,” lead author Sarah Ineson of the UK Met Office told Reuters in an email. The study was published in the journal Nature Geoscience on Monday. (Reuters)

The Sun And The Winter Of 2011
Monday, 10 October 2011 00:01 Dr. David Whitehouse

I’ve said it before. If you are not confused about the Sun’s role in global and regional climate variations, you haven’t been paying attention.

The latest manifestation of the Sun-climate debate takes place in the pages of Nature Geoscience (paywall), here and here. The UK Met Office also issued a press release on the subject a few days ago.

The conclusion is that the Sun’s low activity, in particular its low ultraviolet (UV) output, is influencing the stratosphere in such a way as to produce unusually cold winters in parts of Europe, including the UK.

“Our research confirms the observed link between solar variability and regional winter climate,” lead author Sarah Ineson of the UK Met Office told Reuters. (GWPF)

I’ve Looked at Clouds from Both Sides Now -and Before
Roy W. Spencer

…sometimes, the most powerful evidence is right in front of your face…..

I never dreamed that anyone would dispute the claim that cloud changes can cause “cloud radiative forcing” of the climate system, in addition to their role as responding to surface temperature changes (“cloud radiative feedback”). (NOTE: “Cloud radiative forcing” traditionally has multiple meanings. Caveat emptor.)

But that’s exactly what has happened. Andy Dessler’s 2010 and 2011 papers have claimed, both implicitly and explicitly, that in the context of climate, with very few exceptions, cloud changes must be the result of temperature change only. (Roy W. Spencer)

There is a Greenhouse Effect on Venus

I‘m peppered with emails asking me if articles like this one (which claims there is no Greenhouse Effect at all on Venus) could be right.

Michael Hammer has some 20 patents in spectroscopy, and he explains why the Greenhouse Effect — where CO2 and other gases absorb and emit infra red — is very real, and backed by empirical evidence. The calculations using the Stefan-Boltzmann Law on the atmosphere of Earth and Venus, argue that the Greenhouse Effect is not-detectable. But not-detectable (by that method) does not “prove” the effect is zero. Other methods — like satellite observations of Earth’s atmosphere, and countless lab experiments, tell us that the Greenhouse Effect is real. (The Stefan-Boltzmann Law is used to create the first graph below). Huffman’s calculations suggest other factors are more important than greenhouse gases (with which we heartily agree) and that Hansen et al were barking up the wrong tree by pretending that Venus “shows” us anything much about the Greenhouse Effect. (Indeed, the IPCC mention “Venus” in their first Assessment Report back in 1990 as one of the three key reasons.)

So here in middle-of-the-road centrist land, the people who claim Earth could become more like Venus are wildly exaggerating, but the people who claim that Venus “proves” that the Greenhouse Effect doesn’t exist are just as wrong.

For your average reader, sorry it is esoteric, but there will be avid interest by some science-aficionados in this topic.

– Jo Nova

La Nina Throws Cold Water on Global Warming
By Art Horn

El Nino could become a permanent feature of the Equatorial Pacific Ocean. The warm waters of this never ending hot bath in the world’s largest water body would not only warm the entire earth dramatically, it would pump vast amounts of moisture into the air. This additional humidity would act as a positive feedback mechanism that would enhance the warming already being triggered by human burning of fossil fuels and in turn cause global warming to spin out of control. The melting of glaciers would accelerate and sea levels would rise much faster than predicted. The challenges of runaway warming would not be decades away but would be here now.

Continue reading →

Response To A Question On Skeptical Science On The Fraction Of Positive Radiative Forcing From CO2

Skeptical Science has heeded my request for a more civil debate on the climate issues in their post

Pielke Sr. and SkS Disagreements and Open Questions

This is reaching out to build a bridge to discuss these issues is welcomed.

Today, I will respond to their question:

How did I estimate ~28% as the fraction of the current global annual average human-forced positive radiative forcing? (Roger Pielke Sr.)

Further attempt to falsify the Svensmark hypothesis

Falsification tests of climate hypotheses

The trouble with clouds

Against the Danish physicist’s claim that cosmic rays influence the Earth’s low cloud cover and thereby the climate, there’s one contention that keeps turning up like the proverbial bad penny. During recent years, so the story goes, the Sun has been weak, cosmic rays have been relatively intense, and yet the expected increase in low clouds has not occurred. On the contrary, we’re told, low cloud cover has remained relatively sparse. That’s according the International Satellite Cloud Climatology Project, ISCCP, which pools data from the satellites of several nations,

The contention is repeated in a forthcoming paper in Journal of Climate by Ernest M. Agee, Kandace Kiefer and Emily Cornett of Purdue University, entitled “Relationship of Lower Troposphere Cloud Cover and Cosmic Rays: An Updated Perspective.” An advanced version of the full text is available from: http://curryja.files.wordpress.com/2011/09/agee-cosmic-rays.pdf A favourable commentary appears on the Ars Technica website: http://arstechnica.com/science/news/2011/09/do-cosmic-rays-set-the-earths-thermostat.ars?utm_source=rss&utm_medium=rss&utm_campaign=rss (Calder’s Updates)

New Paper “Influence Of African Dust On Ocean–Atmosphere” By Evan Et Al 2011

There is a new paper that further confirms the importance of the heterogeneous effect of diabatic heating from aerosols, this time from dust, on atmospheric and ocean circulation patterns. We presented the need to assess this regional climate forcing in our paper

Matsui, T., and R.A. Pielke Sr., 2006: Measurement-based estimation of the spatial gradient of aerosol radiative forcing. Geophys. Res. Letts., 33, L11813, doi:10.1029/2006GL025974.

It also confirms the role of human land use change in creating some of this dust. (Roger Pielke Sr.)

Editorial
The Effects of Climate Change on Infectious Diseases: Are they primarily positive, negative or neutral?

Journal Reviews
Interannual Variability of 20th-Century Climate in CMIP3 Models: How good is it? … or, perhaps more appropriately, how bad is it?

Warming of the Tropical Upper Troposphere: How do model simulations of the phenomenon compare with real-world observations?

A Ray of Light Cutting Through the Dark Pall of Flood Damages: Twenty Taiwanese researchers see what few have seen before.

Tibetan Plateau Vegetation: Past, Present and Future: What do we know about the region’s past and present vegetation? … and what does that knowledge suggest about the region’s future vegetation?

Atmospheric CO2 Enrichment and the Weathering of Soil Minerals: Does the former enhance the latter? … and why do we care?

Ocean Acidification Database
The latest addition of peer-reviewed data archived to our database of marine organism responses to atmospheric CO2 enrichment is Blue Mussel [Mytilus edulis] (Bechmann et al., 2011). To access the entire database, click here.

Plant Growth Database
Our latest results of plant growth responses to atmospheric CO2 enrichment obtained from experiments described in the peer-reviewed scientific literature are: Canary Grass (Zhou et al., 2011) and Rice (Kim et al., 2011).

Medieval Warm Period Project
Was there a Medieval Warm Period? YES, according to data published by 1015 individual scientists from 584 research institutions in 44 different countries … and counting! This issue’s Medieval Warm Period Record comes from Rumailiah River Floodplain, North-western Coast of Syria. To access the entire Medieval Warm Period Project’s database, click here.

World Temperatures Database
Back by popular demand and upgraded to allow patrons more choices to plot and view the data, we reintroduce the World Temperatures section of our website. Here, users may plot temperatures for the entire globe or regions of the globe. A newly added feature allows patrons the ability to plot up to six independent datasets on the same graph. Try it today. World Temperatures Database. (co2science.org)