Friday, January 25, 2013

Heat island effect and asthma: an argument for temperature nodes for journalists

Meteorologists shouldn’t be the only people in the news ecosystem concerned with temperature. Extreme temperatures can exacerbate food shortages, hurt the economy, affect energy prices, provoke health crises, cancel public events and disrupt public services.

At the moment, Australia is undergoing the worst heat wave it’s ever recorded. Pavement has melted, and gasoline evaporates right out of the fuel pump, making refueling a car a challenge. Fires are burning out of control in coastal regions. People have died.

It’s gotten so hot (all together now: how hot is it?) that the Australian weather service has added a new color to its heat map which denotes temperatures above 122 degrees Fahrenheit. That’s 50 degrees Celsius, or half the boiling point of water.

This also doesn’t seem like a problem that will disappear in the near future. Climate scientists believe extreme temperatures are only going to be more prevalent. Due to climate change, many parts of the world could experience more extreme high temperatures and fewer extreme low temperatures, with climate models predicting higher maximum temperatures and more heat waves in the future (Easterling et al, 2000).

By some estimates, these heat waves will increase by a factor of 5 to 10 in the next four decades (Barriopedro et al, 2011). Without countermeasures, these high temps could cause “increased adverse health impacts from heat-related mortality, pollution, storm-related fatalities and injuries, and infectious diseases” (Field et all, 2007).

Some might point out that we have a national service that tells us what the temperature is. Election forecasting virtuoso Nate Silver pointed out in his book “The Signal and the Noise” that it’s such a valuable service, in fact, that a multi-billion dollar service industry in weather forecasting has sprung up from the National Weather Service freely sharing its weather data (it should be noted that these services are providing independent forecasts, not simply repackaging NWS data).

In an age where many phones come pre-loaded with weather apps, does it make sense for a publication to have a network of temperature sensors?

For one, many government weather stations that cover metropolitan areas are located at airports. The temperature at a major metro airport can vary from different points within the city.

Additionally, thanks to the heat island effect, temps deep in a city can be as much as 22 degrees higher than less developed regions. All that amounts to more energy consumption, more pollutants, dirtier water, and more health problems. Remember that extreme temperatures can help trigger asthma attacks, and inner city children are already at an elevated risk of having severe asthma (Busse & Mitchell, 2007).

Satellite images obtained of New York City by NASA on August 14, 2002, one of the hottest days of that year. The top image maps out the temperature, while the bottom image maps out vegetation for the city. Note that areas with denser vegetation experienced lower temperatures during the heat wave.

There’s actually a national effort underway to mitigate the heat island effect for cities, with improvements like green roofs, landscape ordinances and green building guidelines.

Wouldn’t it be great to actually get some sensor data to see how the temps in these improved areas compare with the rest of the city? Couldn’t those sensors form part of a network to warn not just ordinary denizens, but those most vulnerable to the health effects of heat waves?

That would be a good use of temperature sensor nodes, and a worthwhile journalism investigation. You could start by scouting for mitigation sites on this map, provided by the EPA.

A network of temp sensors can also keep tabs on microclimates, which are localized climactic conditions near the earth (Geiger, 1965).  According to the NOAA, these microclimates can create differing temperature readings within an area, and even “nearby stations with identical instrumentation and excellent siting can differ by a couple degrees due to local effects.”

Temperature is no trivial matter. It’s important that trained meteorologists tell us what weather will be tomorrow. But it’s also important for journalists to keep tabs on conditions right now, and communicate that data to the public.

Wireless sensor networks are an idea that predates the “internet of things” meme, so the basic concept isn’t something new. Cosm, an online sensor database, was founded as Pachube in 2007. More recently, in April 2012, the Air Quality Egg (AQE) project nabbed $144,000 in funding on Kickstarter.

My hope is that this project (node journalism) will result in a system that is simpler, cheaper, and more suited for the needs of journalists. For the time being, I’ve got a Wifi temperature node set up in an outside location, which is transmitting data to Cosm.

It’s only one data point, but it serves as a prototype and a proof of concept for cheap, rapidly-deployable, internet-capable nodes. Details will be following.