{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2014:YX2E2JLSYB5MW6ZT6FDLEZ4437","short_pith_number":"pith:YX2E2JLS","canonical_record":{"source":{"id":"1401.7368","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ao-ph","submitted_at":"2014-01-28T23:27:08Z","cross_cats_sorted":["physics.soc-ph"],"title_canon_sha256":"c9021fe9775132933c1776b7611f569a565533d2904ee5c238cda3da58665c40","abstract_canon_sha256":"ad7ddc7dbbcf49913a0340a0f56e11a65890ead6e530908a3d98bd0a7e3bbdc1"},"schema_version":"1.0"},"canonical_sha256":"c5f44d2572c07acb7b33f146b2679cdfe2ca89f083a0950bd2b1bbb9c1682502","source":{"kind":"arxiv","id":"1401.7368","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1401.7368","created_at":"2026-05-18T02:50:42Z"},{"alias_kind":"arxiv_version","alias_value":"1401.7368v1","created_at":"2026-05-18T02:50:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1401.7368","created_at":"2026-05-18T02:50:42Z"},{"alias_kind":"pith_short_12","alias_value":"YX2E2JLSYB5M","created_at":"2026-05-18T12:28:59Z"},{"alias_kind":"pith_short_16","alias_value":"YX2E2JLSYB5MW6ZT","created_at":"2026-05-18T12:28:59Z"},{"alias_kind":"pith_short_8","alias_value":"YX2E2JLS","created_at":"2026-05-18T12:28:59Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2014:YX2E2JLSYB5MW6ZT6FDLEZ4437","target":"record","payload":{"canonical_record":{"source":{"id":"1401.7368","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ao-ph","submitted_at":"2014-01-28T23:27:08Z","cross_cats_sorted":["physics.soc-ph"],"title_canon_sha256":"c9021fe9775132933c1776b7611f569a565533d2904ee5c238cda3da58665c40","abstract_canon_sha256":"ad7ddc7dbbcf49913a0340a0f56e11a65890ead6e530908a3d98bd0a7e3bbdc1"},"schema_version":"1.0"},"canonical_sha256":"c5f44d2572c07acb7b33f146b2679cdfe2ca89f083a0950bd2b1bbb9c1682502","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:50:42.529571Z","signature_b64":"15poelA4gPr/zZlj1VzrdpWwhlbJal5OL85oZuBCFrIt+kOxz3o9dm16uD/hUOLN8QECtIISpbeClBsq0GjNAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"c5f44d2572c07acb7b33f146b2679cdfe2ca89f083a0950bd2b1bbb9c1682502","last_reissued_at":"2026-05-18T02:50:42.528966Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:50:42.528966Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1401.7368","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T02:50:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"8OkTTp/gAjlY35q/DCB+4oltE924vSoWdUH0/AqOZ1SnOQj8FQItWXt+DohlARSNMqRGXi+UcP5z3fQOiJD6Ag==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-09T01:57:25.396728Z"},"content_sha256":"016bcd6aae74bc9f7bfc9e6f8f7805981a74437ecb9f6ce5c0423ff8547f60de","schema_version":"1.0","event_id":"sha256:016bcd6aae74bc9f7bfc9e6f8f7805981a74437ecb9f6ce5c0423ff8547f60de"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2014:YX2E2JLSYB5MW6ZT6FDLEZ4437","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Historic Trends in U. S. Drought Forcing in a Warming Climate","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["physics.soc-ph"],"primary_cat":"physics.ao-ph","authors_text":"J. I. Katz, T. Muschinski","submitted_at":"2014-01-28T23:27:08Z","abstract_excerpt":"The mean North American and world climates have warmed significantly since the beginning of climatologically significant anthropogenic emission of greenhouse gases in the 19th Century. It has been suggested that warming may increase the frequency or severity of droughts. We define and study the statistics of an aridity index that describes the precipitation forcing function of a drought, considering drought to be a season with low enough precipitation to be significant for agriculture. Our aridity index is a reciprocal function of the seasonal precipitation, which is more significant for agric"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1401.7368","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T02:50:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"I7AS9NPJAO7FSTddCOUlAohORT++owPBZLtXnW8DjdU1z1xrgcxDDIgESSayEPciDiKQ0a4rsDnakm3lDYNCAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-09T01:57:25.397385Z"},"content_sha256":"88c20e0d2b5fe94f513e537b91b90f42644ecaee0e54711834e71efa98c1ee21","schema_version":"1.0","event_id":"sha256:88c20e0d2b5fe94f513e537b91b90f42644ecaee0e54711834e71efa98c1ee21"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/YX2E2JLSYB5MW6ZT6FDLEZ4437/bundle.json","state_url":"https://pith.science/pith/YX2E2JLSYB5MW6ZT6FDLEZ4437/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/YX2E2JLSYB5MW6ZT6FDLEZ4437/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-06-09T01:57:25Z","links":{"resolver":"https://pith.science/pith/YX2E2JLSYB5MW6ZT6FDLEZ4437","bundle":"https://pith.science/pith/YX2E2JLSYB5MW6ZT6FDLEZ4437/bundle.json","state":"https://pith.science/pith/YX2E2JLSYB5MW6ZT6FDLEZ4437/state.json","well_known_bundle":"https://pith.science/.well-known/pith/YX2E2JLSYB5MW6ZT6FDLEZ4437/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2014:YX2E2JLSYB5MW6ZT6FDLEZ4437","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"ad7ddc7dbbcf49913a0340a0f56e11a65890ead6e530908a3d98bd0a7e3bbdc1","cross_cats_sorted":["physics.soc-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ao-ph","submitted_at":"2014-01-28T23:27:08Z","title_canon_sha256":"c9021fe9775132933c1776b7611f569a565533d2904ee5c238cda3da58665c40"},"schema_version":"1.0","source":{"id":"1401.7368","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1401.7368","created_at":"2026-05-18T02:50:42Z"},{"alias_kind":"arxiv_version","alias_value":"1401.7368v1","created_at":"2026-05-18T02:50:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1401.7368","created_at":"2026-05-18T02:50:42Z"},{"alias_kind":"pith_short_12","alias_value":"YX2E2JLSYB5M","created_at":"2026-05-18T12:28:59Z"},{"alias_kind":"pith_short_16","alias_value":"YX2E2JLSYB5MW6ZT","created_at":"2026-05-18T12:28:59Z"},{"alias_kind":"pith_short_8","alias_value":"YX2E2JLS","created_at":"2026-05-18T12:28:59Z"}],"graph_snapshots":[{"event_id":"sha256:88c20e0d2b5fe94f513e537b91b90f42644ecaee0e54711834e71efa98c1ee21","target":"graph","created_at":"2026-05-18T02:50:42Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"The mean North American and world climates have warmed significantly since the beginning of climatologically significant anthropogenic emission of greenhouse gases in the 19th Century. It has been suggested that warming may increase the frequency or severity of droughts. We define and study the statistics of an aridity index that describes the precipitation forcing function of a drought, considering drought to be a season with low enough precipitation to be significant for agriculture. Our aridity index is a reciprocal function of the seasonal precipitation, which is more significant for agric","authors_text":"J. I. Katz, T. Muschinski","cross_cats":["physics.soc-ph"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ao-ph","submitted_at":"2014-01-28T23:27:08Z","title":"Historic Trends in U. S. Drought Forcing in a Warming Climate"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1401.7368","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:016bcd6aae74bc9f7bfc9e6f8f7805981a74437ecb9f6ce5c0423ff8547f60de","target":"record","created_at":"2026-05-18T02:50:42Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"ad7ddc7dbbcf49913a0340a0f56e11a65890ead6e530908a3d98bd0a7e3bbdc1","cross_cats_sorted":["physics.soc-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ao-ph","submitted_at":"2014-01-28T23:27:08Z","title_canon_sha256":"c9021fe9775132933c1776b7611f569a565533d2904ee5c238cda3da58665c40"},"schema_version":"1.0","source":{"id":"1401.7368","kind":"arxiv","version":1}},"canonical_sha256":"c5f44d2572c07acb7b33f146b2679cdfe2ca89f083a0950bd2b1bbb9c1682502","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"c5f44d2572c07acb7b33f146b2679cdfe2ca89f083a0950bd2b1bbb9c1682502","first_computed_at":"2026-05-18T02:50:42.528966Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:50:42.528966Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"15poelA4gPr/zZlj1VzrdpWwhlbJal5OL85oZuBCFrIt+kOxz3o9dm16uD/hUOLN8QECtIISpbeClBsq0GjNAg==","signature_status":"signed_v1","signed_at":"2026-05-18T02:50:42.529571Z","signed_message":"canonical_sha256_bytes"},"source_id":"1401.7368","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:016bcd6aae74bc9f7bfc9e6f8f7805981a74437ecb9f6ce5c0423ff8547f60de","sha256:88c20e0d2b5fe94f513e537b91b90f42644ecaee0e54711834e71efa98c1ee21"],"state_sha256":"537cbb98a607429e598730aa2e57cbb326c96d10283cb741018ea8cf0df5f39f"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ISnyVeXUy8B60RD1NVscKnOlXN35LHbqgaCIbl+wgb45fOt9ctp6YmSXgQ8bTAw8ByGZOe73UhHzINfNtX4xBQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-09T01:57:25.401248Z","bundle_sha256":"a2fdb24a5ad6c90d34050ef5031e37cf1d482b70e2c74ed1fb0d5cb334d44c3b"}}