Are Public Clouds Elastic Enough for Scientific Computing?

Elasticity can be seen as the ability of a system to increase or decrease the computing resources allocated in a dynamic and on demand way. It is an important feature provided by cloud computing, that has been widely used in web applications and is also gaining attention in the scientific community. Considering the possibilities of using elasticity in this context, a question arises: "Are the available public cloud solutions suitable to support elastic scientific applications?" To answer the question, we present a review of some solutions proposed by public cloud providers and point the open issues and challenges in providing elasticity for scientific applications. We also present some initiatives that are being developed in order to overcome the current problems. In our opinion, current computational clouds have not yet reached the necessary maturity level to meet all scientific applications elasticity requirements.