Vulnerability of London’s Economy to Climate Change: Sensitivity to Production Loss

A variant of the Adaptive Regional Input-Output model (ARIO) has been developed to explore the sensitivity of the London economy to loss of production capacity in sectors affected by climate change related damage. The model is designed for linking to an Event Accounting Matrix (EAM) produced by climate and engineering teams, and then follow this damage through direct and indirect losses in the economy during a recovery process that is either demand-led (in which recovery of production capacity takes place only as demand recovers) or investment-led (where recovery of production capacity can precede demand). Outputs from the model are used to assess the relative vulnerability of London’s economy to production capacity (Capital stock) loss in each of the 42 economic sectors, for purposes of identifying where to most effectively allocate resources to climate change adaptation strategies or to recovery operations when used in conjunction with an EAM. Measures of impact related to GDP loss, recovery time and the ratio of indirect to direct losses are developed for these scenarios. Results show that indirect losses are a significant component of total losses, with a multiplier of between 1.3 and 2 depending on the scale of initial damage.

Neutron transmission imaging with a portable D-T neutron generator

Purpose A portable fast-neutron imaging system is being developed to provide complementary information to field X-ray imaging.Applications include inspection of vehicles and infrastructure for corrosion,measurement of material levels in containers,and inspection of munitions and suspicious packages.While fast-neuron imaging generally provides lower imaging resolution compared to X-rays,fast-neutron interaction cross-sections have a weak dependence on material Z.This enables imaging of low-Z materials inside high-Z materials.Here,we discuss the limitations and current improvements in fast-neuron imaging.Methods Limitations in portable fast-neutron imaging systems include low D-T neutron generator output,low light pro-duction in ZnS(Cu)imaging scintillators,low resolution due to scintillator thickness and D-T spot size,and digital-panel darknoise that varies in time and position and that can be 100×larger than the neutron signal.We have made improvements in these areas through development of a segmented high light yield scintillator,panel noise mitigation techniques,and testing of new high-output,small spot size D-T neutron generators.Results The segmented high light yield fast-neutron scintillator demonstrated 5×increase in light compared to ZnS(Cu).An additional 2×improvement in signal-to-noise was demonstrated with panel-noise mitigation techniques.Our MCNP calculations also show good agreement with neutron imaging results Conclusions We have demonstrated improvements in fast-neutron imaging through development of a segmented high light yield neutron scintillator,mitigation of digital panel noise,and preliminary testing with new high-output,small spot size D-T neutron generators.We have also demonstrated good results modeling fast-neutron images and scatter effects using MCNP.