9.28.2012

Crowd sourcing analysis of tropical cyclones via satellite imagery

Ken Knapp points us to cyclonecenter.org, a new program to crowd-source the analysis of global tropical cyclone records:

Climate scientists need your help classifying over 30 years of tropical cyclone satellite imagery. 
The global intensity record contains uncertainties caused by differences in analysis procedures around the world and through time. Scientists are enlisting the public because patterns in storm imagery are best recognized by the human eye. 
CycloneCenter.org is a web-based interface that enables the public to help analyze the intensities of past tropical cyclones around the globe. The global intensity record contains uncertainties caused by differences in analysis procedures around the world and through time. Patterns in storm imagery are best recognized by the human eye, so scientists are enlisting the public. Interested volunteers will be shown one of nearly 300,000 satellite images. They will answer questions about that image as part of a simplified technique for estimating the maximum surface wind speed of tropical cyclones. This public collaboration will perform more than a million classifications in just a few months—something it would take a team of scientists more than a decade to accomplish. The end product will be a new global tropical cyclone dataset that provides 3-hourly tropical cyclone intensity estimates, confidence intervals, and a wealth of other metadata that could not be realistically obtained in any other fashion.
I use these global records all the time, so I will be personally thankful to anyone who helps improve them.

9.24.2012

"The world's lightest electronic vehicle"


From the project's Kickstarter:
"We have backgrounds in mechanical, electrical, and aerospace engineering from Stanford. We also love longboarding, snowboarding, kiteboarding, and wakeboarding. So it's no surprise that we joined our revolutionary prototype drivetrain with our favorite longboard components. But the bigger picture is even more exciting: changing the world of transportation and shifting the perception of what a vehicle can be. Here's an example. Charge the board every day (6 miles of use). Total electricity cost? Less than $5 per year."
For reference, Wikipedia's description of the last mile problem is short but does the trick. I'm shocked at the amount of power they say the motor generates (2000 watts, or about as powerful as a moped engine).

9.21.2012

Forensic economics

As I suspect is common in my cohort, I have a soft spot for "forensic economics," or economic research that documents illicit behavior. You can feel free to blame it on the popular success of Freakonomics, excess fascination with "clever" papers, peer effects of CSI, etc., but there's certainly something to be said for research which not only discovers something new but does so in spite of others' attempts to conceal it. Which is why I was particularly jazzed about this new paper in the Journal of Economic Literature (open access, btw):
Forensic Economics 
Eric Zitzewitz 
Abstract: A new meta-field of "forensic economics" has begun to emerge, uncovering evidence of hidden behavior in a variety of domains. Examples include teachers cheating on exams, road builders skimping on materials, violations of U.N. sanctions, unnecessary heart surgeries, and racial biases in employment decisions, traffic stops, auto retailing, and even sports judging. In each case, part of the contribution of economic analysis is in uncovering evidence of wrongdoing. Although research questions differ, forensic economic work shares commonalities in approaches and limitations. This article seeks to draw out the common threads, with the hope of stimulating further research across fields.
This is particularly nice since it stretches across fields. Some (quasi-arbitrarily) selected highlights:

9.20.2012

The Anthropocene

If I had to make a movie to advertise this blog and also had animation superpowers, this is the video I would make.

9.19.2012

"Our results add to an emerging literature that documents very high rates of return to small capital investments in developing countries"

Mushfiq Mobarak presented at the Columbia Sustainable Development seminar on Monday, and while I couldn't be there the paper (pdf here) seemed worth passing on:
Seasonal Migration and Risk Aversion 
Gharad Bryan, Shyamal Chowdhury, A. Mushfiq Mobarak 
Abstract: Pre-harvest lean seasons are widespread in the agrarian areas of Asia and Sub-Saharan Africa.  Every year, these seasonal famines force millions of people to succumb to poverty and hunger.  We randomly assign an $8.50 incentive to households in Bangladesh to out-migrate during the lean season, and document a set of striking facts.  The incentive induces 22% of households to send a seasonal migrant, consumption at the origin increases by 30% (550-700 calories per person per day) for the family members of induced migrants, and follow-up data show that treated households continue to re-migrate at a higher rate after the incentive is removed.  The migration rate is 10 percentage points higher in treatment areas a year later, and three years later it is still 8 percentage points higher. These facts can be explained by a model with three key elements: (a) experimenting with the new activity is risky, given uncertain prospects at the destination, (b) overcoming the risk requires individual-specific learning (e.g. resolving the uncertainty about matching to an employer), and (c) some migrants are close to subsistence and the risk of failure is very costly. We test a model with these features by examining heterogeneity in take-up and re-migration, and by conducting a new experiment with a migration insurance treatment.  We document several pieces of evidence consistent with the model.   
Yes, that's $8.50 and 550-700 calories per person per day for family members.

9.14.2012

Temperature, Human Health, and Adaptation

Apropos of last week's post on aggression, Marshall's post on temperature extremes, and this blog's alternate name, please see Olivier DeschĂȘnes' new NBER working paper, "Temperature, Human Health, and Adaptation: A Review of the Empirical Literature":
This paper presents a survey of the empirical literature studying the relationship between health outcomes, temperature, and adaptation to temperature extremes.  The objective of the paper is to highlight the many remaining gaps in the empirical literature and to provide guidelines for improving the current Integrated Assessment Model (IAM) literature that seeks to incorporate human health and adaptation in its framework. I begin by presenting the conceptual and methodological issues associated with the measurement of the effect of temperature extremes on health, and the role of adaptation in possibly muting these effects. The main conclusion that emerges from the literature is that despite the wide variety of data sets and settings most studies find that temperature extremes lead to significant reductions in health, generally measured with excess mortality. Regarding the role of adaptation in mitigating the effects of extreme temperature on health, the available knowledge is limited, in part due to the lack of real-world data on measures of adaptation behaviors. Finally, the paper discusses the implications of the currently available evidence for assessments of potential human health impacts of global climate change.