Dan Cziczo Colloquium Abstract (Apr 19, 2017)

How Our Understanding Of Climate and Precipitation is Influenced by Uncertainties In Particle and Cloud Measurements

Measurements of aerosol particle size, morphology and chemical composition have been conducted in the laboratory for several decades and have now become an almost routine component of ground based and airborne atmospheric research. Satellites are now able to retrieve many relevant properties that are then compared to in situ measurements. Cloud element data – that is, measurements of droplet and ice crystal size and number and determination of the aerosols upon which they form – is not yet as developed as aerosol data but great strides have been made in recent years. When considering both aerosols and clouds we have now surpassed the point of simply “discovering” particle, droplet and ice crystal properties. Instead, we now have sufficient data to start understanding the impact of measurement uncertainty and how it impacts our understanding of climate. This talk will consider how aerosol and cloud measurements are made with a particular focus natural biological aerosols and anthropogenic particles from combustion. We will discuss how misidentification of particles and uncertainty in cloud formation measurements can propagate into global model predications of climate. Finally, suggestions of how to overcome measurement uncertainty and biases in aerosol and cloud measurements will be made.