figure 2a. myth (taken from sankarasubramaniam3).

event radius

sink

figure 2b. Reality (Reventador volcano, 2005; from Werner-allen et al6).

struments, collect as much data as
possible, and then spend a consider-
able amount of time analyzing it and
writing journal papers. After all, data
collection is expensive and time con-
suming, and requires working in dirty
places without a decent Internet con-
nection. Scientists have a vested inter-
est in getting as much “scientific val-
ue” as possible out of a field campaign,
even if this requires a great deal of ef-
fort to understand the data once it has
been collected. In contrast, the sensor
network community has developed a
wide range of techniques to perform
data processing on the fly, aggregating
and reducing the amount of data pro-
duced by the network to satisfy band-
width and energy constraints. Many of
these techniques are at odds with the
domain scientists’ view of instrumen-
tation. No geophysicist is interested in
the “average seismic signal” sampled
by multiple nodes in the network. We
advocate a two-pronged approach to
this problem. The first is to incorpo-
rate large flash memories onto sen-
sor nodes: it is now possible to build
multi-gigabyte SD or Compact Flash
memory into every node, allowing for
months of continuous sensor data to
be stored locally.