Archive for climate change

turning forty…

Posted in Kids, pictures with tags , , , , , , , on July 26, 2019 by xi'an

The previous days have been rather tough thanks to another heat wave all over Europe, with the temperatures at home reaching above 40⁰ (outside) yesterday afternoon and more importantly not getting under 30⁰ inside the house at night, as there was no wind at all to cool it down. (Except in the basement  where I ended up sleeping.) After a certain point, as I am pretty susceptible to hot weather, working became impossible and I spent the rest of the day alternating between drinking cold water, taking cold showers, eating radishes, and watching low intensity movies (like The Crimes of Grindelwald!). The day before, my daughter and I tried a late afternoon trip to the nearby outside pool in the parc but this proved quite a disaster as it was so crowded that it was almost impossible to do laps (in a water of questionable composition). Temperatures are now down a wee bit but I wondering at ways to better insulate our house against what is becoming the new “normal”…. Like installing a massive circus tent every summer.

Nature tea[dbits]

Posted in Books, pictures, University life, Wines with tags , , , , , , , , , , , , , , , , on February 28, 2019 by xi'an

A very special issue of Nature (7 February 2019, vol. 556, no. 7742). With an outlook section on tea, plus a few research papers (and ads) on my principal beverage. News about the REF, Elsevier’s and Huawei’s woes with the University of California, the dangerous weakening of Title IX by the Trump administration, and a long report on the statistical analysis of Hurricane Maria deaths, involving mostly epidemiologists, but also Patrick Ball who took part in our Bayes for Good workshop at CIRM. Plus China’s food crisis and ways to reduce cropland losses and food waste. Concerning the tea part(y), a philogenetic study of different samples led to the theory that tea was domesticated thrice, twice in Yunnan (China) and once in Assam (India), with a divergence estimated at more than twenty thousand years ago. Another article on Pu-Ehr, with the potential impacts of climate change on this very unique tea. With a further remark that higher altitudes increase the anti-oxydant level of tea… And a fascinating description of agro-forestry where tea and vegetables are grown in a forest that regulates sun exposure, moisture evaporation, and soil nutrients.

polluters 3 [taxes] – government 0 [result] – climate minus 1 [or rather +2⁰]

Posted in pictures with tags , , , , , , , , on December 7, 2018 by xi'an

California fires

Posted in pictures, Travel with tags , , , , , , , , on November 17, 2018 by xi'an

“Imagine a leader who defies science, saying these solutions shouldn’t be part of his decision-making on our behalf. Imagine a leader who cares more for his own, convenient option than he does for the people he leads. Imagine an unfit leader. Now imagine a fit one.” Neil Young

Among the many fires that raged and rage throughout the West coast of both US and Canada this year the terrible one that took place in Paradise, near Chico, a few days ago was made much more personal by being the area where we had spent a week on holidays in Lassen National Park. While I think the place escaped the fire, it would be great to hear from the people who hosted us that they are safe… [The quote from Neil Young is related to another fire in Malibu.]

agent-based models

Posted in Books, pictures, Statistics with tags , , , , , , , , on October 2, 2018 by xi'an

An August issue of Nature I recently browsed [on my NUS trip] contained a news feature on agent- based models applied to understanding the opioid crisis in US. (With a rather sordid picture of a drug injection in Philadelphia, hence my own picture.)

To create an agent-based model, researchers first ‘build’ a virtual town or region, sometimes based on a real place, including buildings such as schools and food shops. They then populate it with agents, using census data to give each one its own characteristics, such as age, race and income, and to distribute the agents throughout the virtual town. The agents are autonomous but operate within pre-programmed routines — going to work five times a week, for instance. Some behaviours may be more random, such as a 5% chance per day of skipping work, or a 50% chance of meeting a certain person in the agent’s network. Once the system is as realistic as possible, the researchers introduce a variable such as a flu virus, with a rate and pattern of spread based on its real-life characteristics. They then run the simulation to test how the agents’ behaviour shifts when a school is closed or a vaccination campaign is started, repeating it thousands of times to determine the likelihood of different outcomes.

While I am obviously supportive of simulation based solutions, I cannot but express some reservation at the outcome, given that it is the product of the assumptions in the model. In Bayesian terms, this is purely prior predictive rather than posterior predictive. There is no hard data to create “realism”, apart from the census data. (The article also mixes the outcome of the simulation with real data. Or epidemiological data, not yet available according to the authors.)

In response to the opioid epidemic, Bobashev’s group has constructed Pain Town — a generic city complete with 10,000 people suffering from chronic pain, 70 drug dealers, 30 doctors, 10 emergency rooms and 10 pharmacies. The researchers run the model over five simulated years, recording how the situation changes each virtual day.

This is not to criticise the use of such tools to experiment with social, medical or political interventions, which practically and ethically cannot be tested in real life and working with such targeted versions of the Sims game can paradoxically be more convincing when dealing with policy makers. If they do not object at the artificiality of the outcome, as they often do for climate change models. Just from reading this general public article, I thus wonder at whether model selection and validation tools are implemented in conjunction with agent-based models…

and it only gets worse…

Posted in Kids, pictures with tags , , , , , , , , , , , , , , on October 6, 2017 by xi'an

“An internal Interior Department memo has proposed lifting restrictions on exploratory seismic studies in the Arctic National Wildlife Refuge, a possible first step toward opening the pristine wilderness area to oil and gas drilling.” NYT, Sept 17, 2017

“The Trump administration opened the door to allowing more firearms on federal lands. It scrubbed references to “L.G.B.T.Q. youth” from the description of a federal program for victims of sex trafficking. And, on the advice of religious leaders, it eliminated funding to international groups that provide abortion.” NYT, Sept 11, 2017

“On Aug. 18, the National Academies of Sciences, Engineering and Medicine received an order from the Interior Department that it stop work on what seemed a useful and overdue study of the health risks of mountaintop-removal coal mining.” NYT, Sept 9, 2017

“Last month the National Oceanic and Atmospheric Administration dissolved its 15-member climate science advisory committee, a panel set up to help translate the findings of the National Climate Assessment into concrete guidance for businesses, governments and the public.” NYT, Sept 9, 2017

Climate contrarians, like Trump’s EPA administrator Scott Pruitt and Energy Secretary Rick Perry, don’t understand how scientific research works. They are basically asking for a government handout to scientists to do what scientists are should already be doing. They are also requesting handouts for scientists who have been less successful in research and publications – a move antithetical to the survival of the fitness approach that has formed the scientific community for decades. ” The Guardian, Aug 31, 2017

sinking ever deeper in a bottomless pit…

Posted in Kids with tags , , , , on June 2, 2017 by xi'an