Elsevier has released theirs for economics journals. Here is the top 30:
Journal title 2011 Impact Factor Journal of Financial Economics 3.725 Journal of Accounting and Economics 3.281 Economics and Human Biology 2.722 Social Science & Medicine 2.699 Journal of Banking and Finance 2.6 Energy Economics 2.344 Journal of Health Economics 2.341 Journal of Environmental Economics and Management 2.169 Resources Policy 2.143 Food Policy 2.054 Journal of Monetary Economics 1.892 Journal of Urban Economics 1.892 International Journal of Production Economics 1.76 Journal of International Economics 1.732 World Development 1.537 Journal of Public Economics 1.459 Journal of Corporate Finance 1.447 Review of Economic Dynamics 1.358 Journal of Econometrics 1.349 Futures 1.287 Resource and Energy Economics 1.241 Journal of Economic Theory 1.235 Journal of Financial Markets 1.115 Journal of Economic Psychology 1.069 Economics of Education Review 1.069 Emerging Markets Review 1.067 Journal of Comparative Economics 1.028 Journal of International Money and Finance 1.018 Regional Science and Urban Economics 1.008 Journal of Economic Behavior and Organization 1.006
In contrast, the multidisciplinary Journal of Environmental Management has a 2-year Impact Factor of 3.245, which would put it third on the list. Economics journals must have longer publication lags or research indigestion or something. The 5-year Impact factor of JEM is 3.161 while at JEEM it is 3.060.