Calculation of lava effusion rates from Landsat TM data

Abstract

We present a thermal model to calculate the total thermal flux for lava flowing in tubes, on the surface, or under shallow water. Once defined, we use the total thermal flux to estimate effusion rates for active flows at Kilauea, Hawaii, on two dates. Input parameters were derived from Landsat Thematic Mapper (TM), field and laboratory measurements. Using these parameters we obtain effusion rates of 1.76B0.57 and 0.78B0.27 m 3 s -1 on 23 July and 11 October 1991, respectively. These rates are corroborated by field measurements of 1.36B0.14 and 0.89B0.09 m 3 s -1 for the same dates (Kauahikaua et al. 1996). Using weather satellite (AVHRR) data of lower spatial resolution, we obtain similar effusion rates for an additional 26 dates between the two TM-derived measurements. We assume that, although total effusion rates at the source declined over the period, the shut down of the ocean entry meant that effusion rates for the surface flows alone remained stable. Such synergetic use of remotely sensed data provides measurements that can (a) contribute to monitoring flow-field evolution, and (b) provide reliable numerical data for input into rheological and thermal models. We look forward to being able to produce estimates for effusion rates using data from high-spatial-resolution sensors in the earth observing system (EOS) era, such as Landsat 7, the hyperspectral imager, the advanced spaceborne thermal emission spectrometer, and the advanced land imager.

The airborne lava–seawater interaction plume at Kīlauea Volcano, Hawaiʻi

“…The flux of lava from Puʻu ʻŌʻō was estimated as 3.3m 3 /s for July 2004 and around 6.9m 3 /s for February 2005, based on the volume of magma necessary to account for the emission rate of SO 2 from Puʻu ʻŌʻō [7]. It has been estimated that approximately one third of the extruded volume reaches the sea [26]. The mass of lava required to evaporate 1 kg of seawater is given by:…”

Image‐based measurement of flux variation in distal regions of active lava flows

“…[4] Lava flux estimates are generally made either by relatively direct point measurement of parameters such as flow velocity [e.g., Guest et al, 1987;Lipman and Banks, 1987;Calvari et al, 2002], by differencing sequential topographic fields of the area being analyzed [e.g., Macfarlane et al, 2006;Wadge et al, 2006] or by thermal flux techniques [Harris et al, 1998[Harris et al, , 2000[Harris et al, , 2005. The choice of method depends on the rate and area of change and the measurement frequency required.…”

Early Analysis of Landsat-8 Thermal Infrared Sensor Imagery of Volcanic Activity

“…Indeed, the thermal emissions of an active volcanic surface relate directly to the volcanic activity at a specific time, be it a fresh lava flow, active lava lake or a subtly warm fumarole field [10,11]. Examples of direct relationships between thermal infrared emissions and volcanic activity include the detection of cyclical volcanic emissions related to physical processes on the ground [12], the determination of lava effusion rates (e.g., [13,14]) and the discrimination of different activity styles and lava types [15]. Obviously one significant benefit of such studies is the potential to gather data while avoiding the risks and costs associated with on-the-ground volcanic fieldwork.…”